h+line practical guide for group 2 medical locations€¦ · 2.1.2 medical electrical equipment ......

H+

Lin

e P

ractical guide for group

2 med

ical locations H+LinePractical guide for group 2 medical locations

2CS

C47

0010

B02

01 -

07/

2010

Contacts

ABB SACEA division of ABB S.p.A.Modular DevicesViale dell’Industria, 1820010 Vittuone (MI) - ItalyTel.: +39 02 9034 1Fax: +39 02 9034 7609

bol.it.abb.comwww.abb.com

Data and images are not binding. Depending on technical development and the products, we reserve the right to modify the content of this document without notice.

Copyright 2010 ABB. All right reserved.

Practical guide for group 2 medical locations 1

Practical guide for group 2 medical locations

contents

1 Introduction

1.1 Premise and purpose of the document ......................... 21.2 ABB serving efficiency in the hospital structures .......... 31.3 ABB‘s references in the hospital sector ........................ 4

2 Why it is important to design and implement a system according to the standards

2.1 Definitions and nomenclature ....................................... 6 2.1.1 Medical locations .......................................................... 6 2.1.2 Medical electrical equipment ........................................ 7 2.1.3 Medical electrical systems ............................................ 8 2.1.4 Applied part .................................................................. 8 2.1.5 Extraneous conductive part ....................................... 10 2.1.6 Group 0, 1 and 2 medical locations ........................... 10 2.1.7 Patient environment .................................................... 14 2.1.8 Medical IT System ....................................................... 15 2.1.9 Main distribution board ............................................... 16

3 Implementation of systems in medical locations

3.1 Area of application of the standard ............................ 183.2 Safety prescriptions for medical locations ................. 18 3.2.1 Equipotential bonding ................................................. 21 3.2.2 Medical IT System ....................................................... 27 3.2.3 Insulation monitoring devices ..................................... 31 3.2.4 Insulation monitoring devices for 230 V lines ............ 33 3.2.5 Insulation monitoring devices for 24 V lines .............. 38 3.2.6 QSD remote signalling panels .................................... 403.3 Implementation of the electrical system ..................... 43 3.3.1 Electrical switchboards ............................................... 43 3.3.2 SMISSLINE - Pluggable System ................................ 47 3.3.3 Ducts ........................................................................... 49 3.3.4 Power supply ducts for radiological or similar equipment ................................................... 50 3.3.5 Selectivity of the protection devices .......................... 50 3.3.6 Installation criteria ....................................................... 51 3.3.7 Earthing ....................................................................... 52 3.3.8 Safety services ............................................................ 52 3.3.9 Safety lighting ............................................................. 53

4 Other information on systems for medical locations

4.1 Veterinary premises .................................................... 54 4.1.1 Electrical risk ............................................................... 54 4.1.2 Criteria for sizing and protecting the electrical system ................................................... 55 4.1.3 The Medical IT System in veterinary premises ........... 55 4.1.4 Inspections in veterinary premises ............................. 554.2 Initial and periodic inspections ................................... 56 4.2.1 Initial inspections ........................................................ 56 4.2.2 Periodic inspections ................................................... 61 4.2.3 Recording of the results ............................................. 61

5 Appendix

5.1 Logical path for the design of electrical systems in premises for medical use ........................................ 625.2 Options for design ...................................................... 635.3 Electromedical devices with applied parts ................. 665.4 Laws and decrees ...................................................... 66

2 Practicalguideforgroup2medicallocations

1Introduction

This document is the result of the many years of experience of ABB in the hospital sector and the day-to-day relationship with our customers who operate in this sector, which has made it possible to explore real world issues and applications in depth, while continuously comparing regulatory aspects with technical/installation aspects.We would like to thank all the ABB customers who shared their everyday experience with us for the great sensitivity shown in protecting the safety of the patients.

1.1

Premise and purpose of the documentTheaimofthisdocumentistoillustratetheguidelinesprovidedbyIEC60364-7-710,whicharerequiredfortheimplementationoftheelectricalsystemsinsidegroup2medicallocations:thesetypesofenvironmentsinvolvehighrisksforpatientsand,consequently,requiretheimplementationofadditionalmeasurescomparedto traditionaldomesticandresidentialelectricalsystems.

Thedocumentisalsointendedasanaidtoanyoneapproachingthistypeofsystemforthefirst time, which involves specific design criteria and responsibilities for designers andinstallers.

Practicalguideforgroup2medicallocations 3

1

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1.2

ABB serving efficiency in the hospital structuresImplementingahospitalenvironmentinvolvesknowinghowtochooseandinstallproductswithappropriatecharacteristics.ABBoffersacompleterangeofproductsinthisareaforpreparingeachindividualenvironment,fromoperatingtheatrestoservicerooms,inordertoguarantee thebestpossibleorganisational conditions in hospitals, clinics, retirementhomes,dentalorveterinaryclinicsthatwillenablehealthcarestafftocarryouttheirdutiesefficientlyandtoofferpatientscontinuousandhighqualityassistanceinacompletelysafeenvironment.

Forexample,communicationbetweenpatientsandmedical-nursingpersonnelisguaranteedbythemodernClinos3000system,withdifferentversionsforonlyacoustic-luminouscallsoralsoequippedwiththepossibilityfordirectvoicecommunicationbetweentheindividualpatients and the staff. QSO switchboards are available for the electrical equipping ofoperatingtheatres.ThankstoinsulatingtransformersandISOLTESTERandSELVTESTERdevices,itispossibletoprotectthesystemfromindirectcontacts,withoutautomaticallybreakingthecircuitatthefirstfault.

ABBalsoprovidesalltheproductsandsystemsnecessaryfortheimplementationoftheelectricalsystemsandautomationofthevarioustechnologicalsystemsinthebuilding:fromgeneral electrical switchboards to circuit breakers for controlling lights, from building-automation systems with EIB/KNX systems to high energetic efficiency drive units andmotorsforairconditioningandhydrothermalsystems,fromopenandmoulded-casecircuitbreakerstothewall-mountedandflush-mountedconsumerunits,fromplasticandmetalductstofloorfoundationsystems.Theprotection,command,controlandmeasurementfunctions canbe implemented, not onlybymeansof general-usedevices for electricaldistribution,butalsousingspecificdevices,suchasRCDblocks,RCDs,surgearrestersandahugerangeofDINbarproducts.

All ABB products are designed and manufactured to operate in a perfectly integratedmanner,allowingtheimplementationofthebestsolutionsforoptimisinginvestmentsandmaximizingresultsintermsofquality,costcontrolandoperationalefficiency

Inallsituations,andtomeetallrequirements,choosingABBproductsmeansentrustingtheoperation and management of your systems to a leader company in the energy andautomationsectors,whichhasalwaysbeenintheforefrontofthemanufactureandsupplyofcomponentsandsystemsforhospitalapplications.

> Communicationbetweenmedicalandnursingstaff

> Productsdesignedforintegration


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The Hospital “Circolo e Fondazione Macchi” - Varese

The Hospital “Circolo e Fondazione Macchi” - Varese

1.3

ABB’s references in the hospital sectorThe experience of ABB in the hospital field is based on and certified by a series ofimplementationsthatrepresentthebestfromatechnologicalperspective.The following is a list of the most important hospital structures with which ABB hascollaboratedrecently:•TheHumanitasClinicinRozzano,Milan•TheColumbustreatmentclinic-Milan•TheGaetanoPiniOrthopaedicInstitute-Milan•TheNiguardaCa’Grandahospitals-Milan•SpedaliCiviliinBrescia•The“CittàdiBrescia”hospital,Brescia•TheFondazionePoliambulanzainBrescia•TheOspedalediCircoloandFondazioneMacchi-Varese•TheAostaregionalhospital•TheHospitalCentreofCastelfrancoVeneto,Treviso•TheHospitalCentreofMontebelluna,Treviso


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The Hospital Centre of Castelfranco Veneto (TV)

The Niguarda Ca‘Granda hospitals - Milano

Spedali Civili in Brescia

Spedali Civili in Brescia

6 Practicalguideforgroup2hospitalenvironments

2.1

2Why it is important to design and implement a system according to the standards

IEC 60364-7-710 <Art. 710.2.1

Definitions and nomenclatureBeforeexamining theways inwhichsystems formedical locationare implemented,weprovideanumberofdefinitionsthatwillmakeiteasiertounderstandtheremainingsectionsofthisdocument.

2.1.1

Medical location

location intended for purposes of diagnosis, treatment (including cosmetic treatment), monitoring and care of patients

Medicallocationsmayalsoconsistofagroupofrooms,solongastheyareconnectedfunctionally,evenifnotdirectlycommunicating,andintendedfordiagnostic,therapeutic,surgical,patientmonitoringorrehabilitationpurposes(includingaesthetictreatments)Theoperatingroom,pre-anaesthesiaroom,andwaking-uproomare,forexample,functionallyconnectedrooms.Medicallocationsareenvironmentswithagreaterelectricalriskthanordinary premises because patients may find themselves in conditions of increasedvulnerabilityandsubjecttotheapplicationofelectromedicaldevices.Therefore, particular techniques must be adopted for electrical systems in order toguaranteemaximumsafetyforpatients.

Type of premises Examples Max touch voltage (UL) allowed

Medicallocationsoutpatientsdepartment

25V

ordinaryrooms waitingroom 50V


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Medical locations

Increased electrical risk

Greater protection of safety

Group 2 rooms

Figure 2.1: Medical location (above) and ordinary room (down)

2.1.1continued

Medical electrical equipment

Electrical equipment, provided with not more than one connection to a particular supply mains and intended to diagnose, treat or monitor the patient under medical supervision and which makes physical or electrical contact with the patient, and/or transfers energy to or from the patient, and/or detects such energy transfer to or from the patient. The equipment includes those accessories defined by the manufacturer as being necessary to enable normal use of the equipment.

Thepowersupplycanalsobeobtainedbymeansofaninternalelectricalsource.MedicalelectricalequipmentcanbecategorisedasclassIorclassIIdependingontheirdegreeofinsulation.InclassIdevices,protectionagainstindirectcontactisguaranteedbyconnectiontoasafetyconductor(Fig.2.2.a),whileclassIIprotectionisintrinsicinthatitisprovidedbydoubleinsulationorreinforcedinsulation(Fig.2.2.b).

a

b

Figure 2.2: Medical electrical equipment

2.1.2

> IEC 60364-7-710 Art. 710.2.3


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2.1.3

2.1.4

Medical electrical system

Combination of items of equipment, at least one of which is an item of medical electrical equipment and inter-connected by functional connection or use of a multiple portable socketoutlet. The system includes those accessories which are needed for operating the system and are specified by the manufacturer.

Medical electrical systems are groups of multiple electromedical devices or ofelectromedicaldeviceswithothernon-electromedicaldevices,connectedelectricallybothforthetransferofdataorsignals,andthroughtheirpowersupply.Oneexamplecouldbea device that monitors the physiological parameters of a patient and transfers thecorrespondingdatatoanotherpieceofequipmentwhichinturnprocessestheminordertoprovideinformationusefulfordiagnosis.

Figure 2.3: Medical electrical system

Applied part

A part of the medical electrical equipment which in normal use- necessarily comes into physical contact with the patient for the equipment to perform its function, or- can be brought into contact with the patient, or- needs to be touched by the patient

Theappliedpartcanbeanelectrodeexternalorinternaltothebodyorasurfaceofthedevicethat,forfunctionalreasons,mustbebroughtintocontactwiththepatient.Asregardsthetypeofappliedpart,medicalelectricalequipmentaredividedintodeviceswithpartsappliedoftypeCF,BFandB,classifiedinorderofdecreasingsafety.

Part applied

Symbol Description

CFDeviceswhoseappliedpartisearthinsulated(F=floating)andcanbeplacedindirectcontactwiththeheartsincetheirappliedpartisinsulated

BF

Deviceswhoseappliedpartisearthinsulated(F=floating),butwhichprovidealesserdegreeofprotectionthanCFdevices.Theyarethereforenotsuitablefordirectcardiacapplication

BDeviceswhoseappliedpartisnotearthinsulated.Theyarethereforelesssafeasregardsearthleakage

IEC 60364-7-710 <Art. 710.2.1


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Figure 2.4: Example of an medical electrical equipment with applied part

Figure 2.5: Example of an medical electrical equipment without applied part

2.1.4continued


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2.1.5

Extraneous conductive part

A conductive part that is not part of the electrical system, which can introduce a potential, generally the earth potential.

Examplesofextraneousconductivepartsincludemetalductsforgas,water,forheatingandformedicalgases,theoperatingtable,airconditioningductsandthemetalelementsofthebuilding,suchasmetalwindowframesthatextendoutsidethepremisesorthestructuressupportingtheplasterboardofthewalls.Themetalelementspresent inthepremisesaretobeconsideredasextraneousconductivepartsiftheypresentresistancetoearth:R<0,5MΩ ingroup2medicallocationswhereamicroshockhazardexists (forexample,surgeryroomsingeneral)R<200Ω ingroup1andgroup2medicallocationswherethereisnot,however,

anyhazardofmicroshock,butonlyofmacroshockR<1.000Ω inordinaryrooms

2.1.6

Group 0, 1 and 2 medical locationsTheIEC60346-7classifiesmedicallocationsuseasfollows:

group 0 rooms: medical location where no applied parts are intended to be used.

Theseincludeoutpatientsdepartmentsandmassageroomswhereelectromedicaldevicesarenotused;

IEC 60364-7-710 <Art. 23.3

IEC 60364-7-710 <Art. 710.2.5

Figure 2.6: Group 0 medical locations, outpatients department

1 Conductive parts2 Extraneous

conductive parts3 Extraneous

conductive part (if the table is not electric)


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2.1.6continued

group 1 rooms: medical location where applied parts are intended to be used externally or invasively to any part of the body, except for the cardiac zone.

Theseareroomswhereelectromedicaldeviceswithpartsappliedexternallyoralsointernallytothepatient'sbody-exceptforthecardiaczone-areused;

group 2 rooms: medical location where applied parts are intended to be used in applications such as intracardiac procedures, operating theatres and vital treatment where discontinuity (failure) of the supply can cause danger to life

Thesearepremiseswhereelectromedicaldeviceswithcatheters,withconductivefluidsorelectrodesareapplied in thecardiac zoneordirectly to thepatient'sheart,withaconsequentmicroshock hazard.Group2roomsalso includethose inwhichpatientsundergovitaltreatments,suchthatthe lack of power supply may involve a risk to life,aswellasoperationpreparationrooms,surgicalplasterroomsorpost-operativewaking-uproomsforpatientswhohaveundergonegeneralanaesthesia.

Figure 2.8: Group 2 medical locations, operating room

Figure 2.7: Group 1 medical locations, hospital accommodation room

> IEC 60364-7-710 Art. 710.2.6

> IEC 60364-7-710 Art. 710.2.7


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2.1.6continued

Ordinary roomsTheseareserviceroomsforthemedicalstructure,suchasoffices,roomsforpersonnel(for example, changing rooms, canteen, etc.), store rooms, corridors for access toaccommodationrooms,servicerooms,staffhygienefacilities,waitingroomsetc.

Is it a room intended for medical use, in other words, intended for diagnostic, therapeutic, surgical, patient monitoring or rehabilitation (including aesthetic treatments)?

YES

NO Other type of rooms:for example ordinary

Is at least one medical electrical equipment with applied parts used?

YES

Group 0NO

Are intracardiac interventions or other surgical operations with hazard of microshock performed?

or

is the patient subjected to vital treatments where a lack of electrical power could put the patient's life in danger?

or

Are operation preparation, surgical plaster, post-operative waking-up activities carried out and is general anaesthesia practiced?

Group 1NO

Group 2YES

Theclassificationoftherooms,whichmustbecarriedoutaccordingtothenormaluseoftheenvironment,andtheidentificationofthepatientenvironmentmust be performed by medical personnel orinagreementwiththehealthcareorganization,whichmustindicatewhichmedicaltreatmentsaretobecarriedoutintheroominquestion.In order to identify the group to which the room belongs, risks of macroshock andmicroshockandsituationsofgeneralorlocalanaesthesiamustbetakenintoaccount.

P NMacroshock is identified <with electrocution, in

other words the circulation of current through the body that

occurs when two portions of skin are subjected to a

difference of potential (for example between hand

and hand or between one foot and the other).

In this case the current is divided over several paths

and only one part may involve the thoracic

region and touch the cardiac muscle, and

therefore it can be hazardous for persons in a normal state of health

when it reaches intensities close

to 40 ÷ 60 mA

Figure 2.9: Flow diagram for identifying the type of room


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> Microshock occurs when a difference of potential, which may even be very small, is applied directly to the cardiac muscle through an intracardiac sensor or a catheter (but also a surgical knife that is a good conductor which is accidentally live). In this case, all the current excites the cardiac mass with greater intensity at the point of application of the probe, causing a high probability of triggering fibrillation. The current becomes hazardous if it exceeds 10 ÷ 60 microampere, values that are several thousand times lower than those of the macroshock

2.1.6continued

I

B

P N

Examples of classification of medical locations

Type of room Group 0 Group 1 Group 2

Massageroom

Hospitalaccommodationrooms

Deliveryroom

ECG,EEG,EHG,EMGroom

Endoscopyroom (1)

Outpatientdepartments (1)

Urologyroom (1)

Radiologyandradiotherapydiagnosticrooms

Hydrotherapyroom

Physiotherapyroom

Anaesthesiaroom

Roomforsurgery

Operationpreparationroom (2)

Surgicalplasterroom (2)

Post-operativewakingroom (3)

Roomforapplicationsofcardiaccatheters

Intensivecareroom

Angiographicandhaemodynamicanalysisroom

Haemodialysisroom

Magneticresonanceroom(MRI)

Nuclearmedicineroom

Prematureinfantroom

(1)Ifnotasurgicaloperatingtheatre.(2)Ifgeneralanaesthesiaispracticed.(3)Ifitholdspatientswhiletheyarewakingupfromgeneralanaesthesia.


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Patient environment

Any volume in which intentional or unintentional contact can occur between patient and parts of the system or between patient and other persons touching parts of the system.

Thecentreofreferenceinordertodeterminethepatientenvironmentmaybe,forexample,theoperatingtable,thebedinthehospitalaccommodationroomorthedentist'schair.Thepatientenvironmentdoesnotextendmorethan2.5mabovethewalkingsurfaceandoutsidethepremises.Notethatthepatientenvironmentcanbethecontainerofthepatientenvironmentsrelating to thepositions inwhich thepatientmayreasonablybe locatedwhile in contact with applied parts. Similarly, if there are multiple and/or movableelectromedicaldevices,thepatientenvironmentisextendedtoincludeatmosttheentirepremises.Thereforeaccountistakenofpossiblemovementstowhichtheelectromedicaldevicesorthepatientmaybesubjectedovertime.Determiningthepatientenvironmentduringthedesignphasemakesitpossibletoavoidconnectionoftheextraneousconductivepartslocatedoutsidethepatientenvironmenttotheequipotentialnode,reducingthesizeofthenodeandsimplifyinginstallation,withaconsequentreductionofcosts.Thismeansthereforethatallthepossiblepositionsinwhich thepatientmaybe locatedwhile incontactwithanelectromedicaldevicewithappliedpartsmustbeestablishedinadvance;otherwise,thereisariskthattheelectricalsystemwillbeinadequatewhen,formedicalneeds,itbecomesnecessarytomoveanmedicalelectricalequipmentwithpartsappliedintoapositionotherthanthosepositionsoriginallyenvisaged.Sometimes, therefore, itmaybeopportunetoconsider theentireroomasthepatientenvironment,allowinggreaterflexibilityintheuseofthespaces.

2,5 m

1,5 m

1,5 m 1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m 1,5 m

2,5 m

1,5 m

1,5 m 1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m

1,5 m 1,5 m

IEC 60364-7-710 <Art. 710.2.8

Figure 2.10: Identification

of the patient environment

Can the patient be positioned in

a single predefined position?

Group 2

Room

No patient

environment

Group 1

Group 0

NO

YES

2.1.7


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2.1.8

Medical IT System

Electrical system intended for supply of power supply to the group 2 medical locations.

TheMedicalITSystemconsistsofaninsulatingtransformerformedicaluseandadeviceforpermanentearthinsulationresistancemonitoring.Theinsulatingtransformerprovidestwoessentialfunctions:toguaranteethecontinuityofoperationintheeventofanearthfaultandtoreducethevoltagetowhichthepatientmaybesubjectedsothatitiswithinsafetylimits(andthereforethecurrenttowhichthepatientcouldbeexposed,protectinghim/herfromtheriskofmicroshock).Sinceasecondindirectcontactwouldbeequivalenttoashortcircuit,withtheconsequenttrippingofprotectiondevicesanda serioushazard for thepatient, adevicemustbeassociatedtotheinsulatingtransformerthatcandetectanyreductionininsulationandsignalthefirstearthfault.

subnodo

nodoequipotenziale

subnodo

subnodo

nodoequipotenziale

subnodo

CORRETTO

NON AMMESSO

sub nodoulteriore

LIVELLO 1LIVELLO 0

Equipotential bonding

k

pulsante di prova

Panel with remote signals

Medical insulating

transformer

pulsante ditacitazione

Insulation monitor

test pushbutton

1 2 3 4 5 6

10 11 127 8 9

Power supply

230 V

Medical IT System of the group 2

medical locations

mute pushbutton

test pushbutton

mute pushbutton

> IEC 60364-7-710 Art. 710.2.10

Figure 2.11: Medical IT System


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2.1.9

Main distribution board

A board in the building which fulfils all the functions of a main electrical distribution for the supply building area assigned to it and where the voltage drop is measured for operating the safety services.

Itistheswitchboardpoweredbythemainlowvoltageswitchboardwhichinturnfeedsthezoneanddepartmentswitchboards.Itisintendedforordinaryandsafetydistribution(powersupplybyanelectricity-generatingunitintheabsenceofthenetwork).Thefollowingareinstalledinit:protectionandcut-offdevices, measuring instruments, and possibly an automatic network/generator unitcommutator(whichcould,however,beinsertedalternativelyontheelectricitygeneratorunitswitchboard).The voltage value below which the safety services are activated is measured on thisswitchboard.

MV switchboard

NETWORK

General LV switchboard

Main distribution board (of building)

Medical operators zone

switchboard

Quadro

UPS

Generator unit

switchboard

MT/BT

QDP

Q1

Q2 Q3 Q4 e Q5

Medical IT System

section not Medical IT

System

G

Generator unit

Surgery department

Operating Block

switchboard

Surgery room

switchboard

IEC 60364-7-710 <Art. 710.2.9

Figure 2.12: Example of star distribution of electrical energy in a

hospital structure


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2.1.9continued

Itisadvisable:- thatthemaindistributionboardofthebuildingandthedepartmentandzoneswitchboards

powereddirectlybythemaindistributionswitchboardbelocatedinapositionprotectedagainstfire.

- topositionthedistributionswitchboardforthebuildinginappropriaterooms,notdirectlycommunicatingwith theenvironments intended for thepublicandnot inproximity tocombustiblestructuresortostoresforcombustiblematerial.

Figure 2.13: Example of a main distribution switchboard


3Implementation of systems in medical locations

3.1

Area of application of the standardInmedicallocationsitisnecessarytoguaranteethesafetyofthemedicalpersonnelandinparticularofthepatientswhomaycomeintocontactwithelectromedicaldevices;thereforespecificsafetyprescriptionsmustbeobserved,inadditionaltothegeneralprescriptionsofIEC60364-7-710,concerningboththedevicesandthesystems.Thesafetyofelectricalsystemsinmedicallocationsisthesubjectofsection710ofStandard60364whichappliestohospitals,medicalclinics,medicalanddentalstudios,roomsformassagephysiotherapy,andinallthoseenvironments,wherevertheymaybe(forexample,medicallocationsintheworkplaceorinbuildingsalsointendedforresidentialuse),inwhichelectromedicaldeviceswithpartsapplied to thepatientareused.Theprescriptionsalsoapply topremises foraestheticuse.

3.2

Safety prescriptions for medical locationsThehazardofelectrocutionmayarisefromdirectcontactwithalivepartofthecircuit,orfromindirectcontactwithametalpart,forexamplethemetalbodyofasteriliser,whichisnotnormallylive,butwhichhasbecomeliveduetoaninsulationmalfunction.IEC60364-7-710allowsthefollowingprotectionsystemsagainstdirectandindirectcontactinmedicallocations.

Protection against direct contactForprotectionagainstdirectcontactwithlivepartsonlyinsulationoftheactivepartsorthesegregationthereofthroughtheuseofbarriersorcasingswithaprotectionlevelnolessthanIPXXD(orIP4X)forhorizontalssurfaceswithinreachareallowed,andIPXXB(orIP2X)inalltheothercases.

Protection against indirect contactProtectionagainstindirectcontactinmedicallocationsisbasedonthefollowingprovisions:a) Protectionthroughautomaticidisconnectionofthepowersupply.b) Supplementary equipotential bonding for the conductive parts and the extraneous

conductivepartspresentinthepatientenvironment,orwhichmayenterthezone;c) MedicalITSystem;d) UseofequipmentwithClassIIinsulation;e) Systemswithverylowsafetyvoltage(SELVandPELV).

IEC 60364-7-710 applies <to hospitals, clinics, medical and dental surgeries, rooms for massage physiotherapy,

beauty centres and veterinary surgeries


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Figure 3.1: Examples of type A and type B RCDs

Table 3.2: Maximum interruption times for TN-S systems

Table 3.1: Overview of protective measures against indirect contact

> IEC 60364-7-710 Art. 710.413.1.3

3.2continued

Protective measures Group 1 Group 2

Automaticdisconnectionofthepowersupply

ForallthecircuitsnotpoweredbytheMedicalITSystem

MedicalITSystem

Supplementaryequipotentialbonding

Resistanceofconductors≤0.2Ω

ClassIIdevices Connectionofconductivepartstotheequipotentialbonding

Systemswithverylowsafetyvoltage(SELVandPELV)

Connectionofconductivepartstotheequipotentialbonding

a) Protection through automatic circuit breakingThisprotectionmustbeapplied inawaythat iscompatiblewiththeearthconnectionmethodusedbythenetwork(TNorTT)andbearinginmindthatthevalueofthelimitcontactvoltageUL,intheeventofamalfunction,isreducedto25V(forthesectionofsysteminlowvoltage).

InTN systemsitisprohibitedtouseaPENconductor(TN-Cscheme)downstreamofthemaindistributionswitchboardbecausethiscancausedisturbancesandmayconstituteafirehazard;thereforeonlytheTN-Ssystemisallowed.Inthesesystemsadeadshortearthfaultmustcausethetrippingofprotectiondevices(usuallyautomaticminiaturecircuitbreakers)withinthetimesspecifiedintable3.2.

Voltage U0 (phase-earth) (V)

Terminal circuits t (s)

Distribution circuits t (s)

120 0.4 5

230 0.2 5

400 0.06 5

ThefollowingrelationshipmustbesatisfiedinTT systems:RE · Idn ≤ 25

where:REistheearthresistanceoftheearthplate(inohm);Idn isthehighestnominaloperatingresidualcurrentoftheRCDsthatforprotectionofthesystem(inamperes).Ingroup1medicallocations,thestandardrequiresprotectiononlyoftheterminalcircuitsthatsupplysocketsoutletswitharatedcurrentofupto32A,throughtheuseofresidualcurrentdevicewithIdn≤30mA,althoughresidualcurrenttypeprotectionofallthecircuitsisdesirable.Ingroup2medicalpremisesitismandatoryforallcircuitsthatarenotpoweredbyanMedicalITSystemtobeprotectedbyRCDswithIdn≤30mA(unlessthosecircuitsaresupplyingpowertofixeddevicespositionedataheightabove2.5mandwhichcannotenterthepatientenvironment).

Choosing the Residual Current Device (RCD)Someloads,suchasuninterruptablepowersupplies(UPS),personalcomputers,printers,electromedical equipment, for example devices for computerized axial tomography ormagneticresonance(RM)etc.incorporateelectroniccircuitswhich,intheeventofanearthfault,causecurrentswithcontinuouscomponentsthatcancompromisetheoperationofthenormaldifferentialdevicesof theAC type forprotectingpowersupplycircuits (theindirectcontactcurrentsarenotdetectedbythetoroidaltransformer).This iswhygroup1andgroup2roomsareobliged,dependingonthetypeof leakagecurrent,tousetype ARCDs,whichcanalsointervenewithpulsatingunidirectionalleakingcurrents or type B RCDs also capable of intervening with unidirectional pulsating andcontinuousleakagecurrents.Inthecaseofpowersupplyviathree-phaseUPStheproductstandardrequiresprotectiontobeachievedbymeansofRCDsoftype B.


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3.2continued

Types of RCDs

Simbolo Tipo Applicazione Descrizione

ACGroup1or2roomswithTNdistributionsystem

Onlyworksonlyforearthfaultalternatingcurrents,appliedinstantaneouslyorincreasingslowly

AGroup2rooms:lightingsystemcircuit,radiologicalsockets,socketsforequipmentoutsidebythepatientenvironment

Worksonlyforalternatingandunidirectionalpulsatingearthfaultcurrents,appliedinstantaneouslyorincreasingslowly

B

Worksforalternating,unidirectionalpulsatinganddirectearthfaultcurrents,appliedinstantaneouslyorincreasingslowly

Aunidirectionalpulsatingcurrentisacurrentthatassumesavaluenogreaterthan6mAforanintervalofatleast150°ofeachperiodoftheratedfrequency(at50Hz:8.33ms).

b) Supplementary equipotential bondingIEC60364-7-710prescribesthe implementationofmainequipotentialconnections,atthebaseofeachbuilding,inordertoguaranteetheequipotentialityofalltheextraneousconductive parts entering the same building, and of supplementary equipotentialconnectionsintheenvironmentsatgreatestelectricalrisk.Group1and2medicallocationsareexpresslycoveredbythisprescriptionbecausethedifferencesofpotentialbetweenconductivepartsandextraneousconductivepartsandthereforethecurrentsthatcouldaffectapatientincontactwithsuchconductivepartsarelimitedtothemaximumwiththeadditionalequipotentialconnections.Eachroomformedicalusemustthereforebeequippedwithitsownequipotentialbondingbusbartowhichtheelectricaldevicesandallthemetallicpartsthatcancloseanelectricalcircuittoearthmustbeconnected,sothatifanindirectcontactofadevice(evenexternalto thepremises)occursall theconductivepartsand theextraneousconductivepartsassumealmostthesamepotentialinstantaneously(nosignificantdifferenceofpotentialbetweenthedevicesaccessibletothepatient).Forgroup2medical locations, theequipotentialbondingbusbar resistanceshall notexceed0.2Ω.

c) Medical IT SystemItiswellknownthattheRCDdoesnotlimittheresidualcurrentbutthetimethatitremains(from30to10msapproximately);inthisperiodoftime,althoughverysmall,thevoltagetotheequipotentialnodecanreachhighvaluesandthepatientcanbeinseriousdangerifincontactwiththeconductivepartofthefaultydeviceandanotherconductivepartorextraneousconductivepart.For this reason, ingroup2medical locationswith amicroshockhazard the standardprescribestheuseofanMedicalITSystem,togetherwiththeequipotentialbondingbusbar,forallthecircuitsthatsupplypowerto:-medicalelectricalequipmentslocatedlessthan2.5mfromthewalkingsurface,orwhich

canenterthepatientenvironment;-socketoutletss(exceptforthosethatpowerdeviceswithaconsumptionhigherthan5

kVAandradiologicaldevices).InfacttheMedicalITSystemmakesitpossibleto:-limittheindirectcontactcurrentsbycontainingthecontactvoltages;-reduceleakagecurrents;-guaranteecontinuityofserviceintheeventofafirstearthfaultofadevice.WiththeMedicalITSystem,thecircuitsbranchedtothesecondarymustbeprotectedwithfusesorthermomagneticautomaticcircuitbreakers,butnotRCDsbecausetheRCDwouldnotbeeffectiveinthisparticularsystem.

d) Class II componentsMedicalelectricequipmentstoocanbeimplementedwithinsulationinclassIIandcarrythe“doubleinsulation”symbol.Forthesedevicesthereisnoobligationtoconnectthemtoearthifinstalledinordinaryorgroup1locations;insteadtheymustbeconnectedtotheequipotentialbondingbusbar(ortoasub-node)ifusedingroup2medicallocations.

“Double insulation” symbol

Obligation for <equipotential connections

IEC 60364-7-710 <Art. 710.413.1.2.2.1

Conditions that make <the use of a Medical IT

System mandatory


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Figure 3.2: Equipotential bonding bus bar consisting of a terminal bar

3.2continued

e) Protection against direct and indirect contacts (SELV and PELV systems)Thecombinedprotectionagainstdirectandindirectcontactsisassuredbyverylowsafetyvoltage which can be implemented with SELV (Safety Extra Low Voltage) and PELV(ProtectionExtraLowVoltage)systems,providedthat their ratedvoltage isnothigherthan25Vinalternatingcurrentand60Vinnoninverteddirectcurrent.ThepowersupplymustarrivefromasafetytransformerorfromabatteryandtheSELVandPELVcircuitsmustbe installed inthemannerprescribedby IEC60364-4,clause411.1.Theactiveparts,ifnotadequatelyinsulated,mustbeprotectedwithaprotectiondegreethatisatleastIPXXBand,forhigherhorizontalsurfaceswithinreach(forexample,beds,tablesorothersurfaces),atleastIPXXD.TheuseofthesesystemsinGroup2roomsrequiresthefollowingadditionalprovisions:-the safety transformermustbepoweredat theprimaryby theMedical ITSystem if

devicesthatenterthe“patientenvironment”areconnectedtoSELVorPELVsystems(atypicalcaseisthepowersupplyofthescialyticlampifthisis25V);

-thedevicespoweredmustbeconnectedwith theequipotentialisationsystemof themedicallocations(equipotentialnode).

SELVandPELVsystemsarerarelyused,exceptforsupplyingpowertodedicateddevices,suchasscialyticlightingdevicesorinfusionpumps.

3.2.1

Equipotential node

The function of the equipotential bonding bus bar is to galvanically interconnect all the conductive parts and extraneous conductive parts present or which could enter in the patient environment (fig. 3.2). In this way, if a conductive part malfunction occurs, all the conductive parts will have the same potential and the patient, who may be in contact with two or more conductive parts, is not subject to hazardous currents.The Standards prescribe the installation of an equipotential node bonding bus bar in each group 1 and 2 medical location.

Thenodecanbeimplementedwithaterminalbaroracopperbarwithmultipleholes(oneforeachconductorconnected)andlocatedonawallinsideorimmediatelyoutsidethepremises.Thegeneralrulesapplyingroup0medicallocationsandthereforethereisnoequipotentialbondingbusbarrequired,except,ofcourse,forbathandshowerrooms.

230 V

PE collegamentieventuali

230 V

PE

SELV system

PELV system

230 V

PE possibleconnections

230 V

PE


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3.2.1continued

The elements that may <cause differences on

potential must be connected to the

equipotential bonding bus bar, each with its

own conductor

(1)piping for hot and cold water,drains, oxygen, medical gases,air conditioning, plasterboardsupporting structures, metalfixtures excluding the movingparts such as doors andopenablewindows

(2)sinceinconditionsofuseitcanenterthepatientenvironment

(3)only for group 2 rooms, alsoSELVandPELVdevices

(4)apart from theearthcontactofthe plug sockets positionedabove 2.5 m, used exclusivelyfor supplying power to lightingdevices,whichmusthoweverbeconnectedtotheearthsystem

(5)ingroup2rooms(6)withoutelectricalcomponents

Table 3.3: Elements to be connected and not to be connected to the node

–theconductivepartsandtheextraneousconductiveparts (1)

thatarelocatedinthepatientenvironment,orwhichmayenteritduringuse,includingthoseinstalledataheightabove2.5m,suchastheconductivepartfromthescialyticdevice(2)

–thedeviceprotectionconductors(3)

–theearthcontactsofallthesocketsofthepremises,sincetheycansupplypower todevices thatcouldbebrought into thepatientenvironment(4)

–theironcomponentsofthereinforcedconcreteofthepremises,whenpossible

–anymetalscreenplacedbetweenthewindingsofthemedicalinsulatingtransformer(5)

–anymetalscreensintendedtoreduceelectromagneticfields

–anyconductivegridslocatedunderthefloor

–Non-electricalandfixedpositionoperatingtablesunlesstheseareintendedtobeearthinsulated

–metalfurnitureunits(6)

–metalpartsoffurnishings

Ele

ments

to b

e c

onnecte

d t

o t

he n

ode

Ele

ments

not

to

be c

onnecte

d


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3.2.1continued

Figure 3.3: Example of the elements to be connected to the equipotential bonding bus bar

In the hospital accommodation rooms (group 1 rooms), all the conductive parts andextraneousconductivepartsandanyscreensagainstelectromagneticinterferencemustbeconnectedtotheequipotentialbondingbusbar,becausethepatientenvironmentmustbeconsideredasextendedtotheentireroom.Iftherearebathroomsorshowerroomsfunctionallyconnectedtothegroup1roomsandordinarilyusedbythepatient,thesetoomustbeequipotentialisedthroughthelocalnode.

not required if

H2O / medical gases

if possible

Network

Equipotential bonding bus bar

Patient environment


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3.2.1continued

Sub-nodesIngeneralcascaded connection is not allowed(sub-node),withtheexceptionofmetalpipingandnearbyplugsockets.Only one sub-node maybeplacedintheequipotentialconnectionbetweenaconductivepartorextraneousconductivepartandtheequipotentialnode.Itisalsopossibletohaveseveralintermediatenodesinthesamepremisesaslongastheaforementionedruleissatisfied.Thein-outconnectionbetweensocketsmustbeconsideredasasub-node,andthereforecannotinvolvemorethantwosockets.

sub-node

sub-node

NOT ALLOWEDadditional sub-node

sub-node

equipotential bonding bus bar

equipotential bonding bus bar

sub-node

CORRECT

LEVEL 0

LEVEL 1

Figure 3.4: Correct and not allowed use of sub-nodes


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3.2.1continued

Cross-section of the conductors connected to the equipotential bonding bus barTheconductorsthatconnecttheextraneousconductivepartstotheequipotentialbondingbusbararedefinedasequipotentialconductorsandmusthaveacross-sectionofnolessthan6mm2.Theconductorsthatconnecttheconductivepartstotheequipotentialnodeareprotectionconductors(PE)andtheircross-sectionmustbeestablishedusingthecriteriaspecifiedbythe general standard; in other words, it must be at least equal to that of the phaseconductors.Thecross-sectionoftheconductorthatconnectsasub-nodetotheequipotentialbondingbusbarmustbe at least equal to that of the conductorwith the largest cross-sectionconnectedtothesub-node.

2.5 mm2

4 mm2

6 mm2

2.5 mm2

EQS 6 mm2

EQS 6 mm2

PE 10 mm2

10 mm2

PE

2.5 mm2

6 mm2

6 mm2 4 mm2

10 mm2

Sub-node

Sub-node

Sub-node

Equipotential bonding bus bar

PE

PE

Theequipotentialbondingbusbarmustbeconnectedtothemainprotectionconductoroftheearthingsystemwithaconductorthathasacross-sectionequalatleasttothegreatestofthoseoftheconductorsunderthesamenode.Theprotectionconductorthatactsasthebuildingsupportmustalsohaveacross-sectionthatisnotsmaller.For group 2 medical locations, the resistance presented by the conductor and by theconnectionsbetweenanequipotentialbondingbusbarandaconductivepartorextraneousconductivepartmustnotbegreaterthan0.2Ω.Inthepresenceofsub-nodes,theresistancelimitof0.2Ωreferstotheresistanceofthetotalconnection,alsoincludingtheresistanceofthesub-node.Forgroup1medical locations it isenoughtoensureonlytheelectricalcontinuityoftheconductors.Table3.4providessuggestionson themaximum lengthofprotectionandequipotentialconductorssothattheirresistancewillnotexceedthelimitindicated.

Cross-sectionoftheconductor(mm2) 1.5 2.5 4 6 10

Maximumlength(m) 12 19 31 47 78

Figure 3.5: Minimum cross-sections allowed for equipotential conductors

Table 3.4: Maximum length of the protection and equipotential conductor so that its resistance is no greater than 0.2 Ω


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Identification of the conductors to the equipotential bonding bus barTheequipotentialbondingbusbarmustbeeasytoaccessandtoinspect;forexample,itcouldbeinstalledinaboxbuiltintothewall.It must be possible to disconnect each of the conductors that meet up in the nodeindividually(itisnotallowedtoconnecttwoconductorstosametheterminal)andtheymustbeclearlyidentifiableintermsoffunctionandorigin(itisthereforeadvisedtoidentifythematbothends)inordertofacilitatetesting.Thisidentificationcanbeimplementedwithmarkingsthatspecifytheabovementionedinformationorwithnumberswhosemeaningmustbespecifiedinalistthatisimmediatelyavailable(forexample,appliedtothebackoftheboxcovering).

12

34

5

med

ical

gas

med

ical

gas

med

ical

gas

med

ical

gas

med

ical

gas

12

34

55

655

6

NOT ALLOWED

1= input to equipotential busbar

2= medical gas

3= hot and cold water

4= metallic shields

5= air conditioning

med

ical

gas

Figure 3.6: Identification of the

equipotential conductors by means

of numbering (top figure) and

nameplates (central figure)

3.2.1continued


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3.2.2

Medical IT SystemTheMedicalITsystemisprescribedbyIEC60364-7-710,whichspecifiesthenecessarycharacteristicsofelectricaldistributionsystemsforspecialuses(Section7)andformedicallocations(710).TheMedicalITsystemispoweredwithaspecificinsulatingtransformerformedicalusethathasadeviceforcontinuousmonitoringofinsulationasprescribedbyIEC61557-8.

Medical IT SystemClause 710.2.10 of IEC 60364-7-710 defines the Medical IT System as an electrical system that meets the requirements specified in article 710.413.1.5 as protection for electrical separation with permanent monitoring of the insulation resistance.The Medical IT System is not mandatory, but recommended in group 0 and 1 premises, while in group 2 medical locations it is mandatory in the patient environment, for socket outlets and for fixed equipment within reach.The Medical IT distribution system guarantees operational continuity even in the event of a first earth fault. In a traditional system, as in a domestic scenario, when a malfunction (short circuit, overload or dispersion) occurs, the relevant protection device is tripped. This type of tripping is not suitable for an operating theatre: in the case of a first fault the power supply must be maintained and not interrupted, which could be hazardous since it would involve the interruption of the activities of the doctor and the electrical equipment associated with the patient's health.

Insulation monitoing deviceAn Medical IT System must be powered with an insulating transformer for medical use and must be equipped with a device for permanent monitoring of the insulation, in accordance with IEC 61557-8 Standard. The insulation monitoring device must meet a number of basic requirements:– the a.c. internal impedance shall be at least 100 kΩ;– the test voltage shall not be greater than 25 V d.c.;– the injected current, even under fault conditions, shall not be greater than 1 mA peak;– indication shall take place at the latest when the insulation resistance has decreased to 50 kΩ. A test device shall be providedIt must not be possible to disconnect the insulation monitoring device.

> The Medical IT system guarantees operational continuity in the case of first fault and guarantees the safety of the patient. It is always used in group 2 medical locations


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3.2.2continued

Medical insulating transformers

IEC 60364-7, in clause 710.512.1.6, specifies that:- the transformers must be installed inside or, in the immediate vicinity, outside the

medical locations- the secondary UN rated voltage of the transformers must not exceed 250 V AC- the transformers must comply with IEC 61558-2-15 in as far as applicable. In addition, they must conform to the following prescriptions:- the leakage current of the output winding to earth and the leakage current of the

enclosure, when measured in no-load condition and the transformer supplied at rated voltage and rated frequency, shall not exceed 0,5 mA.

- Single-phase transformers shall be used to form the medical IT systems for por-table and fixed equipment and the rated output shall not be less than 0,5 kVA and shall not exceed 10 kVA.

- if the supply of three-phase loads via an IT system is also required, a separate three-phase transformer shall be provided for this purpose with output line-to-line voltage not exceeding 250 V.

Other prescriptions for transformers: - They must be air cooled- They must have double or reinforced insulation between the windings, and between

these and the conductive part of the equipment;- A metal shield can be placed between the two windings to be connected to earth- The short circuit voltage must not exceed 3%- The no-load current of the primary must not exceed 3%- The peak current must not be greater than 12 times the rated current- The marking of the transformer must bear the symbol:

How to implement the Medical IT System and the parameters recommended by the StandardThe manufacture of insulating transformers must take account of compliance with Standard IEC 61558-1, which specifies the prescriptions relating to the technical requirements specifically for medical insulating transformers. The design must also observe the installation power restrictions established by IEC 60364-7-710, from 0.5 kVA to 10 kVA, with a voltage of 230 V for the primary and 230 V for the secondary. In fact, the use of limited power loads results in:- smaller systems- less users- lower probabilities of failure- easier maintenance- greater redundancy of the circuits- greater continuity of service

In addition, all the prescriptions imposed by IEC 60364-7-710 in this regard must be respected, from the presence of insulation monitoring device, to installation in a permanently monitored location, and the connection of the possible screen of the insulating transformer to the equipotential node in group 1 and group 2 medical locations.The Medical IT distribution system is shunted, in relation to the upstream power supply line, using an insulating transformer for medical use. This galvanically separates the ordinary circuits from the insulated line and eliminates the continuity of the protection conductor.The objective of the structure of these systems is to guarantee the continuation of medical operations after the first fault occurs. Such a situation must, however, be signalled, communicated and monitored in order to repair the first fault condition rapidly, and therefore to avoid a second failure

The characteristics <of these transformers

are specified in clause of IEC 60364-7-710

IEC 60364-7 and <insulating transformers

for medical use


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3.2.2continued

TheoperatingprincipleoftheMedicalITsystemisbasedonthefactthatthecircuitpoweredbythesecondaryoftheinsulatingtransformerisgalvanicallyseparated,whenaconductivepartfirstfaultoccursduetoadefectoftheinsulatorsinaload,thecurrentcannotcontinueto flow in the phase conductors. In this situation all the electromedical devices areoperational.Thefaultmustnothoweverpersistforalongtimebecauseifasecondfaultweretotakenplace,thesafetyandfunctioningofthesystemwouldbecompromised.

ThereisnohazardouscurrentcirculatingonthePEandtheuserdevicesarefunctioningnormally.

TherearenohazardouscurrentsflowingonthePE,butthefirstuserdeviceremainsoutofservice.

BecauseofthecurrentthatflowsonthePE,itisnecessarytodisconnectthepowersupplytotheITnetworksincetheobligationofprotectioncannotbemet.

No fault

First fault

Second fault


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3.2.2continued

ABB’s technological leadership in the hospital sectorWithitsH+LINEproductline,ABBoffersitsexpertiseandtechnicalexperienceinasector,namelythehospitalsector,thatrequiresaveryhighdegreeofinnovationandresearch,aswellasaconstantguaranteeofsafetyandresults.

TI medical insulating transformersThe medical insulating transformers from ABB provide the perfect solution to theserequirements:infacttheycombineStandardscompliancewithmaximumperformanceandminimumdimensions. These small dimensions make it possible contain the costs for theswitchboardsinwhichtheyaretobelocated.Therangeconsistsoftransformerswithpowerconsumptionof3,5,7.5and10kVA,availablewithtwoPT100temperatureprobes,onboththeprimaryandthesecondary.ItsPT100sensors,unlikethePTCtype,aretruetemperaturesensorsandnotsimplethermalalarmsthattripwhenpresetlimitsaresurpassed.PT100sensorsallowconstantandprecisemonitoringofthetemperature,whichcanbedisplayedbytheISOLTESTERinsulationmonitor.Inaddition,thesesensorsallowcompensationoferrorsderivingfromtheintrinsicresistanceofthetemperaturesensorcableitself:theerrorcompensationisusefulthesensorconnectioncablesusedareverylongandtheapplicationrequireshighprecision.An important parameter to evaluate in choosing a device of this type is the thermalinsulation class, that is, how much the product may “heat up” when loaded, whileremaininginconditionsofsafety.ABBtransformersuseaparticularimpregnationsystem,which allows maximum dissipation of heat, thanks to the exclusive vacuum-pressuretechnology.Lastly, the insulating transformer between the two windings has a metal screen thatcontributesinfilteringnetworkinterferenceandtheharmoniccomponentsgeneratedbythepowersupply.

Technical characteristics of IT insulating transformers for medical use

Power kVA 3 5 7,5 10Primaryvoltage V 230 230 230 230Secondaryvoltage V 230 230 230 230Frequency Hz 50-60 50-60 50-60 50-60Secondarycurrents A 13 21.7 32.6 43.5Currentoftheexternalsecondarydelayedfuse T12,5 T20 T32 T40Thermalinsulationclass °C B130 B130 F155 F155Dimensions mm 205x340x150 240x380x150 240x380x160 277x380x260Weight kg 29.5 44 50.5 73Plug-incurrent(peakvalue) <12timestheratedcurrentEarthleakagecurrentofthesecondarywindingandcurrentofdispersionofthecasing(bothwithoutload)

mA <0.5

Maximumambienttemperature °C 40 40 40 40Referencestandards IEC61558-1 IEC61558-2-15 IEC62041Electricalclass 1 1 1 1

TI insulating transformer for medical use ordering codes

Power KVA

PT100 Sensor

Description

Type

ABB Code BbN8012542EAN

3 - TI3 2CSM110000R1541 2896005

5 - TI5 2CSM120000R1541 2896104

7.5 - TI7.5 2CSM130000R1541 2896203

10 - TI10 2CSM140000R1541 2521204

3 n TI3-S 2CSM210000R15a1 2521402

5 n TI5-S 2CSM220000R1541 2521501

7.5 n TI7.5-S 2CSM230000R1541 2521600

10 n TI10-S 2CSM240000R1541 2521709

Figure 3.7: TI insulating transformer


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3.2.3

Insulation monitoring deviceAcurrentoriginatingoutsidetheelectricalsystem,forexampleanearthleakagecurrentcirculating in an electrical device, can cause serious damage because of the greatervulnerabilityofthepatient:insurgicalconditions,acurrentofjusttensofmicroamperesisenoughtocauseventricularfibrillation,whichisnotthecaseunder“normalconditions”,wherethistypeofvalueismoreacceptable.Theleakagecurrentcanbeclassifiedintothreedifferenttypes:-earthleakagecurrent(oftheprotectionconductor)-Fig.3.8.A;-contactcurrent,inotherwordsthecurrentthatcrossesthepersonincontactwiththe

livecasingduetoamalfunctionoftheinsulators-Fig.3.8.B;-leakagecurrentinthecatheterisedpatientandwhichflowstoearth-Fig.3.8.C.

Fig.3.8.A Fig.3.8.B Fig.3.8.C

For each of these there are allowable values that in turn depend on the type ofelectromedical device as established by IEC 60601-1 “Medical electrical equipment -Generalrequirementsforbasicsafetyandessentialperformance”whichappliestomedicalelectricalequipmentsintendedforusebyqualifiedpersonnel,orundertheirsupervision,intheenvironmentsurroundingthepatient,orinrelationwiththepatient,insuchawaythattheydirectly influencethesafetyofpersonsandanimals inthatenvironment.TheStandardspecifiestheprescriptionsforthetransport,storage,commissioning,useandmaintenanceofsuchdevicesintheenvironmentalconditionsspecifiedintheStandardorbythemanufacturer,orprescribedinparticularStandards.Thepurposeistoestablishasatisfactory levelofsafety forall theelectromedicaldevicesused inanenvironmentsurroundingthepatientandtoserveasabasis for thesafetyprescriptionsofspecificstandardsfortheindividualtypesofdevices.

DevicewithpartsappliedoftypeB Lesssafe

DevicewithpartsappliedoftypeBF Safer

DevicewithpartsappliedoftypeCF Evensafer

Leakage current [mA]

Conditions Type of part applied

B BF CF

Toearth(1) Normal 5 5 5

Firstfault 10 10 10

Contact Normal 0.1 0.1 0.1

Firstfault 0.5 0.5 0.5

Inthepatient(2) Normal 0.1 0.1 0.01

Firstfault 0.5 0.5 0.05

(1)ChangedincomparisontoearliereditionsofIEC60601-1.(2)InthecaseofdirectcurrentthelimitsforTypeBandBFappliedpartsareonetenthof

thosespecified.Inaddition,highervaluesareallowedforparticularconditions.

Figure 3.8: Examples of situations that cause leakage currents

Table 3.6: Permissible values for leakage currents (IEC 60601-1)

Table 3.5: Types of medical electrical equipments with applied parts


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3.2.3continued

Characteristics of the insulation monitoring devicePermanentmonitoringofthefirstfaulttoearthmustbecarriedoutusinganappropriateinsulationmonitoringdeviceinsertedbetweenthesecondaryoftheinsulatingtransformerandtheprotectionconductor.Foreachinsulatingtransformerformedicalusetheremustbeaninsulationmonitoringdeviceinordertoimmediatelysignalapossiblefirstfaultandto allow the appropriate maintenance operations necessary to restore the system tooptimalconditions.ThemonitoringdevicemustcomplywiththeprovisionsofIEC61557-8 and must have the following additional characteristics if installed in a medicalenvironment:-internal impedance:not less than100kΩ (measuredbetweensystemterminalsand

earth);-testvoltage:25VDCmax(betweenthemeasurementterminals);-test current: 1 mA DC max (between the system and earth, also in the case of a

malfunction);-impossibilityofdeactivation.Whentheresistanceofearthinsulationdropsbelow50kΩthedevicemustsignalthemalfunction.Itmust,however,bepossibletoverifytheactualoperationalcapacityoftheinstrumentbymeansofatestcircuit

Luminous indications and acoustic signalsTheinsulationmonitoringsystemmustbeequippedwithacousticandluminoussignals.Thisfunctionisperformedbyaremotesignallingpanel,directlyconnectedtotheinsulationmonitor.Thisdevicemakesitpossibleto:-carrythesignaltoseveralpartsofthebuilding;-maketheinsulationmonitorsignalimmediatelyvisiblewhichmaybeinstalledinplaces

inadequatelystaffedbytheappropriatepersonnel(technicalrooms,corridors…);-identifythetypeofalarminprogress(lowinsulation,overloadetc).Thesearethesignalsprovided:-greenindicatorlight(normaloperation);-yellowindicatorlight(insulationhasdroppedbelow50kΩ);-anacousticsignal.Itmustnotbepossible to switchoff ordeactivate the yellow indicator lightwhile themalfunctionremainsonthesystem.Thisisthesequenceofsignalsinthecaseofamalfunction:-theacousticalarmisputintooperation;-theacousticbuzzerissilenced(continuousyellowindicatorlight);-theyellowindicatorlightswitchesoffassoonasnormalconditionsarerestored(after

themalfunctionconditionhasbeenresolved);-interruptionoftheconnectionbetweentheMedicalITsystemorearthandthemonitoring

deviceissignalled.

Lastly,hereareanumberofdesignsuggestions:Itisnotnecessarytoinstallaninsulationmonitoringdeviceifthetransformeronlysuppliespowertoasinglemedicalelectricalequipment;inthiscase,infact,theprobabilityofanindirectcontact(and,evenmoreso,ofasecondindirectcontact)isremote.Inaddition,theshortcircuitderivingfromthesecondindirectcontactwouldnotbeabletocreatehazardousvoltagesontheconductivepartsofotherdevices.Theopticalandacousticalarmsystemshouldnotbeinstalledinjustonelocation;thisallowsthealarmtobeperceivedalsobythosepresentincontiguouspremises.

IEC 61557-8 <

IEC 60364-7 <Art. 710.512

Figure 3.9: QSD remote signalling panels allow medical personnel

to be immediately aware of malfunction situations

Design instructions <


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3.2.4

Insulation monitoring devices for 230 V linesISOLTESTERistheinsulationmonitormanufacturedbyABBandsuitableforinsulatedneutralMEDICALITnetworksforgroup2medicallocationswithanMEDICALITpowersupplysystem.ISOLTESTERmonitorstheearthinsulationoftheelectricalpowersupplygridandtheelectricalor thermal overloading of the transformer, according to the parameters required andrecommendedbyinternationalstandards:-IEC61557-8-IEC60364-7-710-UNE20615.

Insulationresistanceismonitoredbyapplyingameasuringsignalindirectcurrentbetweentheinsulatedlineandearth,andmeasuringtheearthleakagegenerated.Adigitalfilter inserted inthe instrumentguaranteeseffectivemeasurementeven inthepresenceofinterferenceandharmoniccomponents.

ThefourselectionkeysandLCDdisplaymakeiteasytoprogramthedevice,settingthetrippingthresholdswithoutanypossibilityoferror(theconfigurablevaluesarewithintherangeofvaluesspecifiedbytheStandards).ISOLTESTER allows monitoring of the electrical and thermal overload of the medicalinsulatingtransformerbymanagingtwodistincttemperaturethresholdscomingfrombothPT100andPTCsensors.Temperaturemonitoringmakesitpossibletomonitoroverloadingofthetransformerandtoavoidtheautomaticminiaturecircuitbreakerdownstreamofthesecondary.Allmalfunctionconditionsareremotisedthankstoaconnectionwith (upto four)QSDremotesignallingpanels,therebyguaranteeingadequateandprompttechnicalsupervision.Finally,theError-LinkFailsystemexecutesself-diagnosisofthedevicebycheckingthatthewiringattheheadsoftheterminalsispresentandcorrect:thisexcludesthepossibilityofhavingthegroup2medicalroominoperationwithoutthesupervisionoftheinsulationmonitor.

ISOLTESTER-DIG-PLUSadoptsacodifiedsignalwhichguaranteesthereliabilityofthemeasurement in any operational condition, even in the presence of serious networkinterferencegeneratedbytheelectronicequipmentintheroom.Inaddition,itisequippedwithanRS485serialport,thankstowhichthedevicecanbeperfectly integratedwithPLC/PC type communication systems by means of the ModbusRTU protocol. Moreextensivemonitoring ispossiblebecausenetworkminimumandmaximumvaluesaremanaged, which help in diagnosis of the system in the case of a failure. Lastly, aprogrammablerelayallowscompletecontrolofanyalarmconditiondetected.

Figure 3.10: QSO wall-mounted

switchboard

> Reliable measurement in all conditions

> Simple programming with four keys

- Keep the keys – and SET pressed to enter “installation setup” and define the parameters monitored

- Keep the SET key pressed to enter “adjustment setup” and define the threshold values


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Technical characteristics of ISOLTESTER-DIG-RZ

Supplyvoltage 110-230V/50-60Hz

Networkvoltagetobemeasured

24÷230VAC

Maximumvoltagemeasurement

24V

Maximumcurrentmeasurement

1mA

Insulationvoltage 2.5kV/60sec.

Typeofmonitoringsignal continuouscomponentwithdigitalfilter

Measurements insulationmeasurementrange0÷999kΩ/HIGHresolution1kΩtemperaturemeasurementbythermalprobetypePT100with2or3wires-0÷250°C,precision2%currentmeasurementbyA.T.,externalwithsecondary5A,precision2%(ratiovalueselectable1÷200)impedancemeasurement0÷999kΩ/HIGHresolution1kΩ(testsignal2500Hz)

Activationthresholds lowinsulation50÷500kΩ,precision5%,hysteresis5%,configurabledelayovertemperature0÷200°C,precision2%currentoverload1÷999A,precision2%lowimpedance(deactivatable)devicenotconnectedtotheline(linkfail)

Outputsavailable uptomaximumof2panelsatadistanceQSDforsignallingauxiliaryrelayoutputNO-C-NC,5A,250VAC

Displays insulationresistancevaluewithsignallingofavaluebelowthescaleanddeadshortearthfaulttemperaturevaluemeasured0÷200°Cfortrunking1temperaturevaluemeasured0÷200°Cfortrunking2currentvaluemeasured0÷999Ainsulationimpedancevalueprogrammingparametersabsenceofdeviceconnectiontoline(linkfail)relayoutputstatus

Connections maximumconnectablecrosssection2.5mm2

Operatingtemperature -10...60°CStoragetemperature -25...70°C,humidity<90%Dimensions 6DINmodulesWeight 0.5kgCasing self-extinguishingplasticcontainerformountingon

35mmDINrail,withtransparentfrontprotectioncoverwithleadseal

Protectiondegree IP20Powerconsumption 5VA

ReferencestandardsIEC60364-7-710,IEC61557-8,EN60255-6,UNE20615

ISOLTESTER-DIG-RZ Ordering Codes

Description

Type


ISOLTESTER-DIG-RZ 2CSM244000R1501 884507

3.2.4continued

6 modules56

90 45

10544

61

90

6 moduli56

90 45

10544

61

90

Overall dimensions


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Technical characteristics of ISOLTESTER-DIG-PLUS

Supplyvoltage 110-230V/50-60HzNetworkvoltagetobemeasured

24÷230VAC/DC

Maximumvoltagemeasurement

24V

Maximumcurrentmeasurement

1mA

Insulationvoltage 2.5kV/60sec.

Typeofmonitoringsignal codifiedcompoundsignalMeasurementstaken insulationmeasurementrange0÷999kΩ/HIGHresolution

1kΩtemperaturemeasurementbythermalprobetypePT100with2or3wires-0÷250°C,precision2%currentmeasurementbyA.T.,externalwithsecondary5A,precision2%(ratiovalueselectable1÷200)impedancemeasurement0÷999kΩ/HIGHresolution1kΩ(compoundvariablesignal)

Activationthresholds low insulation50÷500kΩ,precision5%,hysteresis5%,configurabledelayovertemperature0÷200°C,precision2%currentoverload1÷999A,precision2%lowimpedance(deactivatable)devicenotconnectedtotheline(linkfail)

Outputsavailable uptoamaximumof4QSDpanelsforremotesignallingprogrammableauxiliaryrelayoutputNO-C-NC,5A,250VACRS485serialoutput,standardModbusRTUprotocol

Displays insulationresistancevaluewithsignallingofavaluebelowthescaleanddeadshortearthfaulttemperaturevaluemeasured0÷200°Cfortrunking1temperaturevaluemeasured0÷200°Cfortrunking2currentvaluemeasured0÷999Ainsulationimpedancevaluevalueoflineearthcapacityprogrammingparametersabsenceofdeviceconnectiontoline(linkfail)relayoutputstatusstorageofmin.valueinsulationandmaxtemperatureandcurrent

Connections maximumconnectablecrosssection2.5mm2

Operatingtemperature -10...60°CStoragetemperature -25...70°C,humidity<90%Dimensions 6DINmodulesWeight 0.5kgCasing self-extinguishingplasticcontainerformountingon

35mmDINrail,withtransparentfrontprotectioncoverwithleadseal

Protectiondegree IP20Powerconsumption 5VA

ReferencestandardsIEC60364-7-710,IEC61557-8,EN60255-6,UNE20615

ISOLTESTER-DIG-PLUS Ordering Codes

Advanced functions Description

Type


RS485,Min/Maxvalues,programmablerelay

ISOLTESTER-DIG-PLUS 2CSM341000R1501 884606

3.2.4continued

6 modules56

90 45

10544

61

90

6 moduli56

90 45

10544

61

90

Overall dimensions


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3.2.4continued

Operation of the front panel operators

5432167

8

9 10 11 12 13

Benefits of ISOLTESTER-ISOLTESTERisdesignedspecificallyforthehospitalenvironment;-asingledeviceallowscontroloftheelectricalandthermalparameters;-itsflexibilityallowstheactivationthresholdstobeadjustedforallthevaluesmonitored;-thereishightolerancefornetworkinterference;-itistherecognisedstandardformonitoringhospitalinsulation;-measurementanddisplayofresistance,primary/secondarytemperature, impedance,

overcurrent;-RS485serialcommunicationportwithModbusRTUprotocol(PLUSversion);-managementofmaximumandminimumparameters(PLUSversion);-insensitivitytonetworkdisturbanceandripples(PLUSversion).

1 3digitdisplay2 GreenLED,SET:instrument

programmingstatus3 YellowLED,Alarm:alarmfora

parametervalueoutsidethethreshold4 RedLED,OutputRelay:auxiliaryrelay

status5 RedLED,Error/LinkFail:alarmfor

internalfailure,noconnectiontothelinetobemonitored,PT100temperatureprobeopenorinshort-circuit

6 RedLED,R:insulationresistance(kΩ)7 RedLED,Z:insulationimpedance(only

forISOLTESTER-DIG-PLUS:insulationimpedanceandcapacityoftheline)

8 RedLED,T1:transformertemperature9 RedLED,T2:2ndsensortemperature10 RedLED,I:linecurrent11 +/-|UP/DOWN:selectionofthe

parametertodisplay,adjustmentofthesettingsanddisplayofthemaximumandminimumvaluesstored(onlyforISOLTESTER-DIG-PLUS)

12 RESET|SET:accesstoprogrammingoftheinstrument,silencingofalarmsanddeletionofstoredvalues

13 TEST|ENTER:testingoftheinstrumentandtheremotesignallingpanelsandconfirmationofSETUPsettings


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3.2.4continued

ISOLTESTER-DIG wiring diagrams

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

RS485(only PLUS

version)

CT .../5 AOut

Link FailInsulation control QSD-DIG 230/24

ISOLTESTER-DIG-RZISOLTESTER-DIG-PLUS

V aux.*115 V 115 V

1 2 3 4 5 6 7 8 9 10 11

QSD-DIG 230/24

V aux. 230 V a.c.

Insulating transformer with PC

IT-M Load

Oth

er Q

SD-D

IG

1 2 3 4

V aux.*115 V 115 V

V aux. 115 V a.c.

PE

PCL

N

SS

PT100 PT1002 1

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

RS485

PT100 PT1002 1 CT .../5 A

Out

QSD-DIG 230/24


V aux.*115 V 115 V

1 2 3 4 5 6 7 8 9 10 11

QSD-DIG 230/24

V aux. 230 V a.c.

IT-M Load

Oth

er Q

SD-D

IG

PE

L

N

SS

(only PLUS version)

Link FailInsulation control

Insulating transformer without PC

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

RS485(only PLUS

version)

CT .../5 A

Out.

QSD-DIG 230/24


V aux.*115 V 115 V

1 2 3 4 5 6 7 8 9 10 11

QSD-DIG 230/24

V aux. 230 V a.c.

IT-M Load

Oth

er Q

SD-D

IG

PE

N

L1

SS

L3

L2

PT100 PT1002 1


Insulating transformer

*connectionoftemperatureprobesandammetrictransformerisoptional

With transformer with central socket (PC)

With transformer without central socket (PC)

With three-phase transformer


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3.2.5

Insulation monitoring devices for 24 V SELV circuitsSELVTESTER-24isanearthinsulationtesterforSELV24VAC/DCcircuits,particularlyrecommendedfor installationinmedical locationsinwhich24Vand230Vlinesexist.ThesystematicandcontinuousmonitoringofthelowvoltagelineintheseenvironmentsisrecommendedbyIEC60364-7-710preciselybecauseafailureorashortcircuitcouldtransferapotentialofmorethan250Vwithconsequentdamagetopersonsandthings.

CharacteristicsSELVTESTER-24monitorstheinsulationresistanceofdedicated24VAC/DCcircuitsforpoweringascialyticlamp.Itisimportanttomonitortheinsulationofthescialyticlampbecauseconductorscouldbecomedetachedandenterintocontactwiththemetalstructurewhilethelampisbeingmanoeuvred.SELVTESTER-24measuresthevariationofthepotentialofthetwonetworkpolaritiesinrelation to the earth, and signals a decrease in resistance below a predefined value,allowingimmediateinterceptionofthemalfunction.Inadirectcurrentsituationitisalsopossibletodiscernthepolarityinvolvedinthefailure.TheoutputsignalcanbecarriedremotelyinroomswiththegreatestmedicalstaffpresencethankstoremotesignallingpanelscalledQSD-DIG230/24.ThefrontoftheSELVTESTER-24includesatestpushbutton,statusindicatorandtwoLEDsforalarmscausedbylowinsulation.Microswitchesallowtheactivationthresholdtobevaried(10….50kΩ).TheTESTpushbuttonperformstheperiodiccorrectoperationtest.

Technical characteristics of SELVTESTER

Networkvoltageandauxiliarypowersupply

24V50-60Hz/DC±20%

Max.loss 3VA

Measurementcurrent max.0.5mA

Internalimpedance 50kΩ

Activationthresholdsettingadjustable10÷50kΩ(4levelsbymeansofmicroswitches)

Activationdelay approx.1s

Signals ONLED,ALARM+LED,ALARM-LED

OutputFormax.2QSD-DIG230/24remotepanelsMax.24V1A

OperatingtemperatureStoragetemperature

-10÷60°C-20÷70°C

Relativehumidity ≤95%

Insulationtest 2.5kV60s/4kVimp.1.2/50µs

Crosssectionofterminals 4mm2

Protectiondegree IP40frontpanelwithcover/IP20container

Modules 3

Weight 200gapprox.

ReferencestandardssafetyIEC61010-1productIEC60364-7-710electromagneticcompatibilityIEC61326-1

SELVTESTER-24 Ordering Codes

Monitored network Description

Type


SELVinsulatedline24VAC/DC

SELVTESTER-24 2CSM211000R1511 884705

44

58

85,5

52,5

45

3 modules

85,5

44

58

85,5

52,5

45

3 moduli

85,5

Overall dimensions


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3.2.5continued

1 2

3

4

Benefits of SELVTESTER-Overalldimensionsofonlythreemodules-Immediateinstallation;-Settingoftheactivationthresholdtothemostcommonlyusedvalue;-Recognitionofthefaultypolewhenoperatingunderdirectcurrent.

Wiring diagrams


IT-M Load

Oth

er Q

SD-2

30/2

4-C

PE

L(+)

N(-)

SS

1 2 3 C1 C2 C3 C4 X Y Z

QSD-DIG 230/24

1 2 3 4 5 6 7 8 9 10 11

SELVTESTER-24

1Green LED ONIndicationthattheinstrumentisfunctioning

2Yellow ALARM LEDsLowinsulationalarmsignal;inthecaseofalinetobemonitored,withalternatingcurrentthetwoLEDslightup,whereaswithdirectcurrentonlytheLEDofthepolaritybelowtheactivationthresholdlightsup.

3Test pushbuttonInstrumentfunctiontest

4 MicroswitchesThefrontmicroswitchesallowthethresholdtobesetintherange10to50kΩ,asshowninthediagram.


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3.2.6

QSD remote signalling panelsItoughttobepossibletosendanalarmcausedbyapossiblemalfunctionfromadistance,sothatitisimmediatelyobvioustomedicalpersonnelandspecializedtechnicians.TheQSDremotesignallingpanelsalsoreportalarmsignalsrelatingtoa lowinsulationsituationor in the caseof electrical or thermal overloadof the transformer,making itpossibletoidentifythetypeoffault.

CharacteristicsQSD-DIG230/24controlpanelscanbeinstalledeasilyinuniversalflush-mountedboxeswiththreemodules.Theyhavea testpushbutton forperiodicallychecking theiroperationandasecondpushbuttonthatallowsthesimultaneoussilencingoftheacousticsignalofallthepanelsthatmaybeconnectedtothesameISOLTESTERinsulationmonitoringdevice.WithQSD-DIG230/24itispossibletodistinguish,evenremotely,thetypeofalarm;inother words whether it is caused, for example, by low resistance, an overload or anovercurrent(identificationofthemalfunctiontype).QSD-DIG230/24wasdesignedtobefullycompatiblewithallABBinsulationmonitorsfor230and24Vlines,bothcurrentlymanufacturedmodelsandearlierversions:

Typeoflinemonitored 230V 24V

insulationmonitoringdevicesISOLTESTER-DIG-RZISOLTESTER-DIG-PLUS

SELVTESTER-24

Phased-out insulation monitoringdevices

ISOLTESTER-RZISOLTESTER-C

SELVTESTER-C

Wiringcanbecarriedoutwithacommon0.35mm2cable,whichguaranteessignalcoveruptoadistanceof300m.QSD-DIG230/24conformstothefollowinginternationalreferencestandards:-IEC612010-1;-IEC61557/8;-IEC60364-7-710;-UNE20615;-IEC61326-1(Electromagneticcompatibility).

Technical characteristics QSD-DIG 230/24

Signals

greenLEDnetwork,redLEDoverload,yellowLEDfaultbuzzer2400Hzintermitting2HzdB

Pushbuttons test(TEST),acousticsilencing(MUTE)

Crosssectionofterminals 2.5mm2

Protectiondegree IP30

Installation universalflush-mounted3modulesbox

Weight 200g

Operatingtemperature -10÷60°C,maxhumidity95%

Storagetemperature -25÷+80°C

Insulation 2500Vrms50Hzper60s

Minimumcross-sectionofthecable 0.35mm2(300mmax)

Referencestandards

safetyIEC61010-1productIEC61557-8/IEC60364-7-710IEC60364-7-710UNE20615electromagneticcompatibilityIEC61326-1

QSD-DIG 230/24 Ordering Codes

Compatibility Description Type


Universal QSD-DIG230/24 2CSM273063R1521 730637

A single panel <for universal

remote signalling

Reference standards <for QSD

17

55

121

78 78

17

55

121

78 78

Overall dimensions


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3.2.6continued

3

4

1

2 5

Advantages of the product-Smalldimensions-Canbeinstalledinauniversalflushmountedbox-Immediaterecognitionofthetypeofmalfunction-Simultaneoussilencingofmultiplesignallingpanels-Operationalefficiency

Wiring diagrams

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

RS485(only PLUS

version)

CT .../5 AOut

Link FailInsulation control QSD-DIG 230/24


V aux.*115 V 115 V

1 2 3 4 5 6 7 8 9 10 11

QSD-DIG 230/24

V aux. 230 V a.c.

Insulating transformer with PC

IT-M Load

Oth

er Q

SD-D

IG

1 2 3 4

V aux.*115 V 115 V

V aux. 115 V a.c.

PE

PCL

N

SS

PT100 PT1002 1

ISOLTESTER-DIG

1 Testpushbutton2 Acousticsilencerpushbutton3 GreennetworkLED4 OverloadalarmredLED5 MalfunctionalarmyellowLED


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LF-PE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18LF-L VC-L VC-PEAUX-L1 AUX-01 COM-P V-PFAULT

Vaux:* Pannellocontrollo remoto

19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

Out

ISOLTESTER- C

1 2 3 4 5 6 7 8 9TEST+TEST-

10 11ACKACUS OVER COM-PV-P FAULT

QSD-DIG 230/24

PE

PC

SS

IT-M LOAD

Vaux: 230Va.c.

230V

L

N

OTHERQSD-DIG 230/24

COM-S F-S TEST-SR-NO R-CR-NC



1 2 3 4 5 6 7 8 9PE

10 11V-

SELVTESTER-24

V+

PE

SS

IT-M LOAD


L(+)

N(-)

QSD-DIG 230/24

1 2 3 4 5 6 7 8 9

OTHERQSD-DIG 230/24

OUT-NO OUT-NCOUT-C10 11

TEST+TEST-ACKACUS OVER COMPV-P FAULTCOM-S F-S TEST-S

3.2.6continued

SELVTESTER-24

ISOLTESTER-C ISOLTESTER-DIG-RZ


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3.3

Implementation of the electrical systemToimplementtheelectricalsysteminmedicallocationsboththegeneralprescriptionsofIEC60364aswellasthespecificprescriptionsofsection710,includedintheseventhpart,mustbeobserved.The main best technique rules are specified below concerning switchboards for thedistributionofenergywithinahospitalstructureandtheinstallationofsystemsingroup2rooms.

3.3.1

Electrical switchboardsAlltheelectricalswitchboardsmustconformtothesafetyprescriptionsofStandardsIEC60439-1and3.Inenvironmentsformedicaluse,dependingontheirsize,ismaybenecessarytousethefollowingtypesofelectricalswitchboards(fig.3.11):-generallowvoltage(QGBT);-formaindistributioninthebuilding(QDPE);-fordepartment(QR);-forsurgeryroom(QSO).

Operat.theatreA Operat.

theatreB

QR

QDPE

QR

QR

Depart. CQDPE

QGBT

QDPE

QR

QR

QSOQSO

QR

QDPE

MV/LV main

switchboard

Entrance - Offices

Pavilion 1

Pavilion 2

Depart. B

Depart. A

Depart. F

Depart. D

Themainswitchboardandthedistributionswitchboardforthebuildingshouldbelocatedin specific rooms, not directly communicating with the environments intended for thepublicandnotinproximitytocombustiblestructuresorstoresforcombustiblematerial.

Protection degree of switchboards

Per la protezione contro i contatti diretti Protezione contro le influenze esterne

IPXXD(IP4X)

forhorizontalsurfaceswithinreach IPX4inroomswherefluidsarenormallyspilt

IPXXB(IP2X)

foralltheothercases IPX5inroomsfortheuseofjetsthatmustbecleanedwithwater

Figure 3.11: Representation of the star distribution system used in healthcare structures

> Types of electrical switchboards


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3.3.1continued

General LV switchboardSwitchboardforordinaryenergydistribution(fromthenetwork)inwhichthefollowingmay,forexample,beinstalled:-generalprotectionandsectioningdevices;-measuringinstrumentsandremotemonitoringdevices;-protection devices for the lines that supply power, for example, to: auxiliary cabinet

services;theauxiliaryelectricity-generatorunitservices;themaindistributionlinestothebuildings; the distribution lines of services external to the buildings; the technologicalstations(airconditioningsystem,thermalandwaterstation).

Main distribution switchboard of the buildingSwitchboardforordinaryandsafetydistribution(throughtheelectricity-generatingunit)inwhichthefollowingareinstalled:-generalprotectionandsectioningdevices;-measuringinstrumentsandremotemonitoringdevices;-protectiondevices,preferablysuitableforsectioning,forthelinesthatsupplypowerto

appliancesthatrequirepowerfromanelectricity-generatingunit(fire-preventionsystem,liftingsystems).

Department switchboardsThedepartmentswitchboardscanbethesameasthemainswitchboardsofthebuilding.Iftheseswitchboardsarelocatedinsidethepavilionordepartment,theyshouldpreferablybelocatedinaspecialroom.Theyarerecommendedtohaveglass(ortransparentplasticmaterial)doorstofacilitatecheckingthestateofthedevices.Thedestinationsof the lines leaving the switchboarddependon the functions that thedepartmentcarriesout.

Switchboards for surgery roomsForgroup2surgery rooms, inaddition to theswitchboard for thepowersupplyof theordinary circuits, a switchboard for supplying power to the Medical IT system is alsonecessary(fig.3.12).ItisalsoallowedtouseasingleswitchboardthatgroupstheMedicalITsystemequipmentandthepowersupplyequipmentforalltheotherappliancesintotwodistinct sections. In the absence of the ordinary power supply, the switchboard mustcommutatedontothesafetypowersupplyprovidedbyanuninterruptiblepowersupply(UPS).

Socket group

Socket group

Socket group

Diaphano-scope

Anae-sthetist’s pensile

sockets (1)

Surgeon’s pensile

sockets (1)

Scialytic lamp

power supply

Fixed operating

table

Reserve

1 2 3

24 V Line

5 QSD230/24-C

4

3

3

Id

Auxiliary line

2

QSD-DIG230

6

(1)Thesocketsoftheanaesthetistandsurgeonpensilesarepoweredbymultiplelines

1Surgearrester2Insulatingtransformer3TemperatureprobePT1004Insulationmonitoringdevicefor230V

circuit5Insulationmonitoringdevicefor24V

circuit6Transformer220/24V-1kVA

Figure 3.12: Switchboard for the Medical IT system power supply.


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3.3.1continued

InthiswaythecontinuityofserviceofalltheMedicalITpowereddevicesinthepremisesisimprovedandhighqualitypowersupplyfortheelectromedicaldevicesparticularlysensitivetothevoltageandfrequenciesisguaranteed.Inthecaseofasingleswitchboard,subdividedintotwosections,thefollowingcomponentsareinstalled:-ageneralsectioningdevice;-RCDsoneachoutboundconnectionandwithIdn≤30mA,andoftypeAorBforthe

ordinarypowersupply;-adeviceforprotectionagainstovercurrentsupstreamoftheinsulatingtransformer;-possiblyacircuit-breakerdownstreamoftheinsulatingtransformerforprotectionagainst

the overloads in the case where there are no temperature sensors on the insulatingtransformer

-theMedical ITsystemdevices(insulatingtransformer,permanent insulationmonitoringdevicewithopticalandacousticsignalling).

-protectiondevicesagainstovercurrentsofthelinesthatsupplypowertotheplugsocketsandofanyotherfixeddevicesoftheMedicalITsystem.

Theequipotentialnodeoftheswitchboardcouldbeusedastheequipotentialnodeofthepremisesifitcomplieswiththeprescriptionsofthestandards.

Choice of power consumption of the medical insulating transformerThepowerconsumptionoftheinsulatingtransformerdependsonthetypeofpremisesinquestion,thepowerconsumptionoftheconnectedloadsandonmaintenanceandcontinuityofservicerequirements.Onaverage,theMedicalITsystemsuppliespowertoatleast6groupsofsockets:-2socketgroupsavailabletothesurgeon-2socketgroupsavailabletotheanaesthetist-2wall-mountedsocketgroups.Forverylargecardiacsurgeryroomspowerconsumptionofupto15kVAcanbeenvisaged,andthereforetwo10kVAinsulatingtransformersareusedsoastohaveasurplusofpowerthatwillallowfor futureexpansion.Onetransformercansupplypower towall-mountedsocketswhiletheothercanpowerthesocketsofthepensiles.Innormaloperatingroomsoroutpatientdepartmentsthepowerofthetransformerdropsto7.5-5-3.5kVA.Inanycase, it isalwayspreferabletooverestimatepowerconsumptiontoenablefutureexpansionwithouthavingtomodifythesystem.

Section “E”(Emergency)

Section “S”(Safety)


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Technical characteristics of QSO switchboards

Ratedvoltage [V] 230±15%ACRatedfrequency [Hz] 50Numberofphases 1+N~/PERatedvoltageofauxiliarycircuits [V] 230ACRatedinsulationvoltage [V] 300-2,500Referenced earth distributionsystem

TT/TN-S

Max.short-circuitcurrent [kA] 6symmetricRMSMaxaltitude [m] 2000abovesealevel

Pollutiongrade1nopollutionoronlydry

andnon-conductivepollutionShockresistancedegree IK09

ProtectiondegreeIP65frontpanelwithdoor

IP31frontpanelwithoutdoorIP20onthetop

Relativehumidity 50%Operatingtemperature [°C] -5/+40Storagetemperature [°C] -25/+55Referencestandards IEC60364-7-710IEC60439-1

QSO Ordering Codes

Power KVA

PT100 Sensor

SELV 24 V Line

Description

Type


Wall-mounted electrical switchboards for operating room3 - - QSO3kVA 2CSM110000R1551 2376101

5 - - QSO5kVA 2CSM120000R1551 2376200

7.5 - - QSO7.5kVA 2CSM130000R1551 2376309

3 n - QSO3kVA-S 2CSM210000R1551 2526308

5 n - QSO5kVA-S 2CSM210000R1541 2526407

7.5 n - QSO7.5kVA-S 2CSM230000R1551 2526506

Floor-standing electrical switchboards for operating room3 n - QSO3kVA-S-PV 2CSM310000R1551 2526605

5 n - QSO5kVA-S-PV 2CSM320000R1551 2526704

7.5 n - QSO7.5kVA-S-PV 2CSM330000R1551 2526803

10 n - QSO10kVA-S-PV 2CSM340000R1551 2526902

3 n n QSO3kVA-S-PV+24VAC 2CSM410000R1551 2614302


7.5 n n QSO7.5kVA-S-PV+24VAC 2CSM430000R1551 2614500


3.3.1continued


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3.3.2

SMISSLINE - Pluggable System. Keeps downtime to a minimum SMISSLINE allowed a high maintenance of electrical systems. Wherever availability is necessary in 365 days at 24 hours a day the pluggable system gives a maximum on Flexibility.SMISSLINE protection devices are simply snapped into a plug-in socket system. Thearduoustaskofpowersupplyandconnectionisdone.Inadditiontosavingsintimeandmoney, another advantage of the system is the quick and easy exchangeability of thedevices.Ifthecorrespondingsparecapacityisplanned,subsequentexpansionconsistsmerelyofplugginginandconnectingadditionaldevices.

Equipment AvailabilityAdditions, expansionsandmodificationsofpanelboardsareeasilydone thanks to themodularstructureofthissystem.Costsanddowntimearelimitedtoaminimum.The SMISSLINE plug-in system really comes into its own when safety, availability andversatilityareessentialrequirementsinstructures.

System Overview

7

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3 29 26

11

3031

30

27

24

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1319

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2624

1 Supplyterminal2 Incomingterminalblockwitha

max.currentratingof160A50mm2(2x25mm2)+2x10mm2(LA,LB)

3 Coverforincomingterminalblock4 Supplycable5 SurgearresterOVR4046 RCBOFS4017 Residual-currentcircuitbreakerF4048 MiniaturecircuitbreakerS401M9 Signalcontact10 Plugcontacts11 DINadaptor12 Sparewaycover13 Devicelatch14 BusbarL3orDC+,–15 BusbarL2orDC+,–16 BusbarL1orDC+,–17 BusbarN18 Sockets,8-moduleand6-module19 AuxiliarybusbarLA20 AuxiliarybusbarLB21 BusbarN,external22 BusbarPE,external23 Additionalsocket24 NandPEterminals32A1mm2to

10mm2,63A16mm2to50mm2and100A16mm2to95mm2,redandorangeterminalsforDC

25 Outputcircuits26 Busbarisolator27 Dummyblockand18mmcoverwith

DINtopfortheadditionalsocket28 Socketendpieceonleftandright29 Incomingterminalcomponent,centre

powersupply200A,maximum95mm2

30 Universaladapterwithacurrentratingof32A,63Aor100A

31 Combimodulewithacurrentratingof32A


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Pluggable devices on the SMISSLINE SystemMiniature circuit breaker S4001-,2-,3-and4-poledeviceswithacurrentratingBetween0.5Aand63ACharacteristicsB,C,D,K,UC-Z,UC-CSnaponauxiliaryandsignalcontactsontheleftandrightRatedswitchingcapacityIcn:6kA(E)and10kA(M)Residual current device F402, F4042-poleresidual-currentcircuitbreaker25Ato40A,10,30,100mA4-poleresidual-currentcircuitbreaker25Ato63A,30,100,300mAShorttimedelaytypeFIK(doesnotreacttodischargecurrents)Selectiveresidual-currentcircuitbreakertypeS(selectivetoFIorFIK)

Combined RCBO FS401, FS403RatedbreakingcapacitykA(E)and10kA(M)Snap-onauxiliaryandsignalcontactsontheleftShorttimedelayedversionsFIK(doesnotreacttodischargecurrents)

Surge arrester 404 OVR4-poleprotectiondevice,type2Potential-freesignalcontactintegratedinthedeviceRateddischargesurgecurrentIsn15kA

Motor protection circuit breaker MS 325PowermotorprotectioncircuitbreakerMS325Un690V,In0.1to25A,breakingcapacity100/50kA,withphasefailureprotection,temperature.

Auxiliary and signal contactsTheplug-insocketsystemgivesyoutheoptionofsignalingviaauxiliarybusbars.TheauxiliarybusbarsLAandLBcanbecontacteddirectlyviacontactingparts.ThecontactingpartscanbeeasilychangedfromLAtoLBbyrepluggingthem,ortheycanberemovedcompletely.Acollectivealarmispossibleusingtheinnovativecollectivealarmsignalcontact.Todothis,contactismadeparallelwiththeauxiliarybusbars.

Advantages of vertical construction compared to conventional layoutsLargerassemblieswithSMISSLINEcanbearearrangedvertically.Thepowerfortheplug-insocketsystemissuppliedviaanincomingterminalblock.Fewercablesarerequiredforthecrossconnectionsinthecontrolcabinet.Theinputwiringisintegratedintheplug-insocketsystem.TheNandPEterminalsaredirectlyassignedtothedevices.Theoutgoingcablesareconnecteddirectlytothedevices.Thisresultsinanoverallcleararrangement.Expansioniseasythankstotheplug-intechnology.

Customer Benefits with SMISSLINE in Hospitals and ClinicsReliability and AvailabilityFastandeasyhandlingwithpluggabledevicesPlug-intechnologyprovides24-hourservice,365daysayearFreedom in concept and designMixofdevices,variouspowersupplyoptionsFlexiblearchitecturewithoutriskofdamagetolifeandpropertyUpgradeabilityEasyintegrationofnewdevicesUpgradewithoutchangingtheexistinginstallation

3.3.2continued


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3.3.3

DuctsIngroup2medicallocationstheductsinstalledinsidetheroommustbepurposedexclusivelyforthepowersupplyoftheelectricaldevicesandtheiraccessoriespresent inthesameroom;inpractice,ductsthatsupplypowertoequipment locatedinotherroomscannotpassthroughthesegroup2medicallocations.ThecircuitsbranchingfromanMedicalITsystemmustnecessarilybeseparatedfromtheelectricalcircuitspoweredbyothersystems,andmust,therefore,beinstalledinseparatepipingorductsandboxes.Theuseofsharedductsandboxesisalsoallowedprovidedthattheseparationisimplementedwithaninsulatingseparator(fig.3.13).

.........................

Insulatingseparator

IT-Msystem circuit

Insulatingseparator

IT-Msystem circuit

Ordinarycircuit

Ordinarycircuit

ThecircuitsoftheMedicalITsystemcanalsobeimplementedusingunipolarcables(cords)ofthetypeN07V-K(withthewarningnottousenavy,blueorlightblueconductors,sinceanMedicalITsystemneverhasNeutral).If it is impossibleto implementaphysicalseparationoftwoelectrical systems,andtheMedical ITcircuit runs throughaduct “shared”with theconductorsofanothersystem,doubleinsulationcableswithanon-metallicsheathmustbeused.Inaddition,iftheleakagecurrentisduetoacapacitiveeffect,itisrecommendedthattheprotectionconductorbeseparatedfromthephaseconductorsandtheninsertedinitsownprotectivetube.

Ingroup2medicallocationswhereelectromedicaldevicesareusedinordertomonitorandsupport vitalparameters, suchas thoseof intensivecare, resuscitationandsimilar, thedevicesshouldbepoweredusingconductorsthatareshieldedorinsertedinmetallicpipingasaprecautionagainstelectricalfields.Boththeshieldingsofthecablesaswellasthemetalpipingmustbeequipotentialisedonthenearestnodeorsub-node.ForradiologyandCATroomsandroomswithequipmentthatemitsionisingradiation,thepowersupplyconductorsshouldnotinterrupttheradiationshieldingspresent.Theprotectionof theductsagainstovercurrentsmustbe implementedusingomnipolarautomaticminiaturecircuitbreakers.AlsoinMedicalITsystems,thecircuitsbranchedtothesecondarymustbeprotectedwithfusesorthermomagneticautomaticminiaturecircuitbreakers,butnotwithRCDsbecause theRCDwouldnotbeeffective in thisparticular“medicalinsulation”system.

Figure 3.13: Separation of Medical IT circuits from others by means of insulating separators


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Power supply ducts for radiological or similar equipmentRadiologicaldevicesandthosewithapowerconsumptioninexcessof5kVAabsorbhighvaluecurrentsfromthepowersupplyline.Forthisreasonthesizingofthepowersupplyconductorsmustbeassessedcarefullyinordertocontainvoltagedrops.Radiologicaldevicesofthefixedtypeanddeviceswithpowerconsumptiongreaterthan5kVA,powereddirectlybythe“ordinary”networkandingeneralwithouttheinterpositionofasocket/pluggroup,canbeprotectedwithRCDswithadifferentialcurrentof0.5A.If they may enter the patient environment it is mandatory to adopt differential 30 mAthermomagnetic miniature circuit breakers of type “A” (for single phase circuits) or “B”(especiallyforthree-phasecircuits).

3.3.5

Selectivity of the protection devicesParticular care must be taken in implementing effective selectivity of the overcurrentprotectiondevicesinordertoguaranteemaximumcontinuityofservice.Asfaraspossible,horizontalandverticalselectivitymustbeimplemented.Withhorizontalselectivity,andthereforebysubdividingthesystemintodifferentcircuits,downtimeinthecaseofamalfunctionisreduced.Subdivisionintoseveralcircuitsalsomakesitpossibletoprevent thesimultaneoususeofnumerousdevicesconnected to thesamecircuit fromcausingthetrippingoftheRCD(forexampleduetothecapacitiveearthleakagesofthedevices).Aparticularaspectofhorizontalselectivityconcernsgroup2rooms:thestandardsrequirethatforeverypatienttreatmentposition(suchasasocketcontrolpanel,awall-mountedpowersupplyunitorthepensilestand)theplugsocketspoweredbytheMedicalITSystemmustbealternatively(fig.3.14):– connected to two distinct power supply circuits (each equipped with the respective

protectiondevice);– protectedagainstovercurrentsindividuallyoringroups(atleasttwo).Withthisprovision,ifaplugsocketdownstreamfails,withtrippingoftherelatedprotectiondevice,onlyonesocketoronegroupofsocketswillbeoutofservice,whiletheothersremaininoperation.Togetherwithhorizontalselectivityitisalsonecessarytoguaranteeverticalselectivitysothat,intheeventofovercurrent,onlythedeviceforprotectionofthecircuitaffectedbythemalfunctionwilltrip,andnotdevicetheupstream(fig.3.15).

Medical ITSystem

Medical ITSystem

Medical ITSystem

SistemaIT-M

SistemaIT-M

SistemaIT-M

a b c

OnlythisMiniaturecircuitbreakermustbetripped

3.3.4

Figure 3.14: Protection of sockets powered by the Medical IT Systema) subdivision into two separate

circuits protected individuallyb) protection in groupsc) single protection

Figure 3.15: Vertical selectivity in the presence of Miniature

circuit breakers in series.


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3.3.5continued

SelectivityinMedicalITcircuitscanbeimplementedwiththermomagneticswitchesorfusesofadequatesize.Whenusingfuses,theirpurposeistoprotecteachsocketinthegroupand,upstreamintheroomswitchboard,toprotectthepowersupplyductforeachgroupofsockets.Totalselectivityisimplementedbychoosingfusesoftheappropriatesizeandthemainswitchwithaveryhighmagnetictripcurrent.Theadvantagesareobvious: if oneconsiders that a short circuit in anoperating roomnormallyoccursbecausetheplugshavebeenpulledoutbytuggingthecableinsteadofgraspingtheactualplug,orduetofluidsenteringintocontactwithactiveparts,ashort-circuitonasocketcausestrippingoftherespectivefuses,andthereforeitispossibletouseanothersocket(therearealwaysmoresocketsthannecessary)withoutanyseriousdisservice.Withtheuseofautomaticminiaturecircuitbreakers,selectivitycanbeobtainedbychoosingtheprotectiondevicessothatforalltheshortcircuitvalues,uptothemaximumleakagecurrentprovidedforontheductprotectedbythedownstreamcircuit-breaker,thetrippingzones of the miniature circuit breakers in series do not overlap (fig. 3.16). In general,however,selectivitybetweencircuitbreakersisobtainedalsobyregulatingtheirtrippingtimedelays.

time

miniature circuit breaker 1

miniature circuit 2



miniature circuit breaker 1 maximum assumed short circuit current

miniature circuit 2

current

SelectivitymustalsobeimplementedfortheRCDsassignedtoprotectequipmentpowereddirectlybythenetwork.Forexample,inthehospitalaccommodationrooms(group1rooms)therearethreecircuits(lighting,plugsockets,headboardsockets)eachprotectedwitha30mARCD;toprotectthepowersupplycircuitsforagroupofrooms,a300mARCDisinstalled,whileupstreaminthecabinetthereisa500mARCD.Lastly,totalselectivityisobtainedbyregulatingthetrippingtimedelaysoftheRCDs.

3.3.6

Installation criteriaTheswitchboardcontainingtheinsulatingtransformercanbeinstalledeitherwall-mountedorfloor-standingoutsidegroup2rooms,or insideprovidedthat it isoutsidethepatientenvironment,inordertoavoidcontactbetweenthepatient-includingviamedicalpersonnel–andthecabinet,whichcontainsnotjustthecircuitsdownstreamofthetransformer,butalsoitspowersupplyconductors.If the requirements demand power higher than that allowed (10 kVA) for the insulatingtransformer,thenmultipleinsulatingtransformersmustbeinstalledinordertocontaintheleakagecurrents.Inthiswayitispossibletobenefitfromtheredundancyofthecircuitsinordertomaximizecontinuityofservice,alsointhecaseofmaintenance.TheinsulationmonitoringandmeasuringdevicecanbeplacedintheelectricalswitchboardoftheMedicalITsystem,butapanelwithrepetitionofacoustic/opticalsignalsandatestpushbuttonmustbelocatedinthemostusedpremises,wherethecontinuouspresenceofhealthcareoperatorsisassumed.Boththeplugsocketsandtheminiaturecircuitbreakersmustbeinstalledatmorethan20cm(fromcentretocentre)fromanyconnectionforgasformedicaluse.TheplugsocketspoweredbyanMedicalITsystemmustnotbeinterchangeablewiththeplugsocketsofthesamepremisesthatarepowereddirectlybythenetwork.

Figure 3.16: Total selectivity between two miniature circuit breakers in series.


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3.3.7

EarthingIngroup1and2premisesonlythefollowingappliancesmaybeconnecteddirectlytotheprotectionconductor(alltheothersmustbeconnectedtotheequipotentialnode):-fixedappliances,suchasceilinglightingappliancesinclass0andI,aslongastheyare

installedmore than2.5mabove thewalkingsurfaceorcompletelyoutside thepatientenvironment;

-limitersagainstovervoltagesofanyorigin(itisadvisabletoinstallthemontheincominglinesthatsupplypowertothemedicallocations).

3.3.8

Safety servicesInmedicallocationsitispossibletousedevicesforwhichtotalavailabilityofthepowersupplyisrequiredinordertoavoidhazardsforthepatientinthecaseofmalfunctionsinthesystemorthedevices,orintheeventofablack-out.Toobtainoperationalcontinuityfollowingamalfunction,itisrecommendedtouseaninsula-tingtransformereveningroup1medicallocations,inoutpatientdepartmentsandinlabora-tories,sinceitguaranteestheuseofelectricaldevicesevenifa“firstearthfault”occursinoneofthese.Inanalysislaboratoriesinparticular,continuityisanessentialfactorbecauseinthecaseofaninterruptionintheenergysupplyalongtimeisrequiredforreprogrammingandrecommissioningthem.Todealinsteadwithaninterruptionofthepowersupply(black-out)anemergencysystemmustbeinstalleddedicatedtothesafetypowersupplyfortheloadsdefinedasprivilegedbecausenecessaryforthesafetyofthepatient.Thecharacteristicsofthesafetypowersupplymustbeestablishedbythedesigner,takingaccountoftherealrequirementsofthehealthcarestructuretobeservedandthestandardsinforce.Inallgroup2(andinsomegroup1)medicallocations,thesafetypowersupplymustbeau-tomaticwithashortinterruption(≤0.5s)andmustguaranteethepowersupplyofthelightingdevicesforoperatingtables,theelectromedicaldevicesthatrequireasafetypowersupplyandthemonitoringandalarmsystemsforatleastthreehours.Forotherservicesandelectromedicaldevicesthesafetypowersupplycanhaveamediuminterruptiontime,inotherwordswithanactivationtimenolongerthan15s(safetylightingforexitroutes,electromedicaldevicesetc.),oralonginterruptiontime,greaterthan15s(sterili-zationdevices,refrigeratorsetc).Thesafetysourcemayconsistofbatteries,uninterruptablepowersupplies(UPS)orelectricity-generatingunits.IneachoperatingroomorgroupofroomscontinuityofoperationshouldbeimplementedwithatleasttwoUPS.Inthisway,eachUPSworksat50%ofitspower,andisnotthereforesubjecttooverloadsandcanstandinfortheotherintheeventofmalfunctions.TheuseofmultipleredundantUPSalsobenefitsmaintenance,whichcanbecarriedoutononegroupatatime,thusallowingtheoperatingroomtoremainactive.AfurtheradvantageofferedbytheUPSisthequalityoftheenergysupplied,witharesultingabsenceofinterferenceonthecircuitsdownstream.TheUPSareablesupplypowertotheloadwithoutanyinterruption,buttheynormallyhavelimitedautonomy(10÷30min)andthereforeanelectricity-generatingunitintervenesafter-wards(fig.3.17).

Network Electricity-generating unit

Ordinaryloads

Privilegedloads

Lightingsystem

Medical ITloads

To the operating theatre

Figure 3.17: Safety power supply implemented with a UPS and an

electricity-generating unit.

Necessity for continuity <of operation


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3.3.9

Safety lightingSafetylightingisrequiredinthefollowingenvironments:-group1andgroup2medicallocations.-exitroutesandsafetyexits,includingtheassociatedsafetysigns;-roomscontainingcabinets,electricalswitchboards,productionsystemsources;-rooms with essential services, such as elevator machinery, kitchens, air conditioning

stations,dataprocessingcentres;Safety lighting must enter into operation within the times specified by the standard(table3.7).Safetylightingmustbeguaranteedviacentralizedsystems(batteriesorelectricity-generatingunits)orbymeansofautonomousdevices, individuallyequippedwithabatterywithanautonomyofatleast2hours.The tablespecifies the tripping timedelays for thesafetypowersupply requiredby thestandardinrelationtothetypeofmedicalpremises.

Type of premises Interruption

≤ 0,5 sInterruption

≤ 15 sMassageroom (1)

Hospitalaccommodationrooms

Deliveryroom (2)

ECG,EEG,EHG,EMGroom

Endoscopyroom (2)

Outpatientdepartments (1)

Urologyroom

Radiologydiagnosisandradiotherapyrooms

Hydrotherapyroom

Physiotherapyroom

Anaesthesiaroom (2)

Roomforsurgery (2)

Operationpreparationroom (2)

Surgicalplasterroom (2)

Post-operativewakingroom (2)

Roomforapplicationsofcardiaccatheters (2)

Intensivecareroom (2)

Angiographicandhaemodynamicanalysisroom (2)

Haemodialysisroom

Magneticresonanceroom(MRI)

Nuclearmedicineroom

Prematureinfantroom (2)

(1)Onlyforgroup1medicallocations.(2)Lightingdevicesandelectromedicaldeviceswitha lifesupport functionthat requirea

powersupplywithin0.5sorless.

Table 3.7: Tripping time delays of the safety power supply in relation to the type of medical premises


4Other information on systems for medical locations

4.1

Veterinary premisesArea of application of the standards to veterinary premisesTheIEC60364-7-710specifiesthatasfarasitispracticallyapplicable,thestandardcanalsobeusedforveterinaryclinicsandsurgeries”.Veterinaryenvironmentscanhavevaryingdegreesofriskdependingonthefunctionthattheveterinarymedicalmanagerwishestoassigntohisstudioortothestructureinwhichhecarriesonhisactivity.Itisthereforetheveterinarymedicaldirectorwhomustdefinetheactivitycarriedoutinthevariouspremisesbymeansofawrittendeclaration;thedesignerdefinesthesystemstobeimplementedonthebasisofthedirector'schoices.

4.1.1

Electrical riskRegardingelectrocutionphenomena(directandindirectcontacts)animalspresentahigheror lower riskaccordingto thespecies toyoutowhich theybelong, theirsizeandthetreatmentsoroperationstowhichtheyaresubjected,andincertainconditions(includedheartoperationsonanimalsforresearch)theymayalsobesubjecttotheriskmicroshock.Theriskofmicroshock isnormallyparticularlysignificant inveterinaryclinics,hospitalsandresearchcentres.Inveterinarystudiosandlaboratories,ontheotherhand:-intracardiac operations or operations that may involve the cardiac muscle are not

performed;-electromedicaldeviceswithappliedpartsareusedwithgreatmoderation,while“electrical

devices”areused frequently,aswellas theiraccessoriessuchasshearingdevices,portableelectricdrills,asare“electromedicaldevices”suchasfixedortrolley-supportedscialyticlampsthatenterthepatientenvironment.

Figure 4.1: Example of a veterinary clinic


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4.1.1continued

Wecanthereforeconcludethatveterinarystudiosandlaboratoriescanalwaysbeconsideredasgroup1evenifsurgicaloperationscanbecarriedoutinthem,whilegroup2locationscanbepresentinveterinaryclinics,universityhospitalswithveterinaryspecialisationandinveterinaryorclinico-pharmacologicalresearchcentres.

Is it a premises where the veterinary examines the animal without using electrical devices, even if not strictly electromedical devices with applied parts (for example, electric razors) or which may enter the patient environment (for example, scialytic lamp)?

YESGroup 0 veterinaryroom (including animal accommodation rooms)

NO

Is the animal subjected to therapy and/or treatmentincluding invasive surgical operations using electrical or electromedical devices with applied parts or that enter the patient environment, but the risk of microshock is low?

YES Group 1 veterinarylocations

NO

Is the animal subjected to cardiac operations or treatment that could result in high risks ofmicroshock?

YESGroup 2 veterinarylocations also with a hazard of microshock

4.1.2

Criteria for sizing and protecting the electrical systemTheprotectivemethodsadoptedforthelocations,asspecifiedbytheIEC60364-7-710,canalsobeappliedtoveterinaryrooms,classifiedaspreviouslymentioned.

4.1.3

The Medical IT system in veterinary roomsTheMedicalITsystemcanbeadoptedfordifferentrequirementsdependingonthegrouptowhichtheveterinaryroombelongs. If theroomisdeclaredasgroup2(microshockhazard) thesystem ismandatory. If the roombelongs togroup1 theadoptionof theMedicalITsystemmaybeadvisableinordertoguaranteethepossibilityofusingcertainelectricaldevicesevenifa“firstearthfault”occursinoneofthese.Theadoptionofadevice thatmonitors the insulationof thepartofsystemunder theinsulatingtransformer ismandatory forgroup2roomsandrecommendedforgroup1rooms.

4.1.4

Inspections in veterinary premisesAs for premises for human medical use, in the case of veterinary premises it is alsomandatorytoperformtheinitialandperiodicinspectionsaccordingtotheprovisionsofthestandards.

Figure 4.2 shows a flow diagram for choosing the group of the veterinary premises.


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4.2

Initial and periodic inspectionsTheelectricalsystemsinmedicallocationsmustbeinspected,bothbeforecommissioningand also after any modifications or repairs (initial inspections); thereafter, they must becheckedatintervals(periodicinspections)pre-establishedbyatechnicalexpert,whomayormaynotbeanemployeeofthehealthcarestructure,andtheresultsofeachinspectionmustberecorded.

4.2.1

Initial inspectionsThe electrical systems of group 0 rooms (ordinary systems) are only subject to theinspectionsrequiredbyIEC60364.Forthesystemsofthegroup1andgroup2rooms,inaddition to thechecksrequired forordinarysystems, the followingchecksmustbeperformed:

Tests and checks to be carried out Group 1 premises

Group 2 premises

1 FunctionaltestsontheinsulationmonitoringdeviceandtheopticalandacousticalarmsystemoftheMedicalITsystem

–

2 Measurementoftheleakagecurrentsofthesecondaryno-loadwindingandonthecasingofthetransformersformedicaluse;thetestisnotnecessaryifithasalreadybeencarriedoutbythemanufacturerofthetransformer

–

3 Measurementoftheresistanceofthesupplementaryequipotentialconnections

–

4 Checkofthecontinuityoftheprotectionandequipotentialconductors

–

5 VisualinspectiontoensurethattheotherregulatoryprescriptionsspecifiedbySection710ofStandard60364-7havebeenrespected

Thechecksarecarriedoutonthebasisofthedesigndocumentationwhichmustincludeatleast:-floorplansindicatingthegrouptowhicheachmedicalpremisesbelongs;-floorplansindicatingthepositionoftheequipotentialnodeswiththerelatedconnections;-thewiringdiagrams.

Functional testing of the Medical IT systemThe functional testof the insulationmonitoringdevice iscarriedout throughaseriesofassessmentsfollowedbyanumberoftests.

- the device must conform to the IEC 61557-8, concerning devices for testing, measurement and monitoring protective measures;

- the internal impedance of the device must not be lower than 100 kΩ;

- the supply voltage of the alarm circuit must not be higher than 25 V DC.

Initial assessments

Tests

a) measurement of the current circulating in the alarm circuit that, even in the event of a malfunction, must not be higher than 1 mA DC;

b) check that the alarm signal occurs when the insulation resistance drops below 50 kΩ.

Instrumentation <To carry out the tests and

measurements appropriate instrumentation is

required, including:- a Voltmeter;

- a milliammeter grip;- a milliohm meter with a

no-load voltage between 4 and 24 V in DC or AC and

test current of 10 A;- a device for testing the

circuit breakers


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Figure 4.4: Insulation controller trip test

Figure 4.3: Measurement of the current in the alarm circuit.

4.2.1continued

a) Measurement of the current in the alarm circuit

Purpose of the test: Itmustguaranteedthat,eveninthecaseofamalfunction,thecurrentinthecircuitdoesnotexceedthevalueof1mADC.

Instrument:milliammeter.

Procedure:measurementofthecurrentinthealarmcircuitcanbecarriedoutinconditionsofdeadshortearth faultby inserting themilliammeter inserieswith theconductor thatconnectsthedevicetotheequipotentialnodeandconnectingoneoftheconductorsoftheisolatedcircuitdirectlytoearth(fig.4.3).

insulating transformer

network 230 V/50 Hz

dead short connection

I 1 mA

insulation monitoring device

to the equipotential bonding bus bar

b) Trip test

Purpose of the test:tocheckthattheinsulationmonitoringdeviceisfunctioningcorrectly,inotherwords,thatthealarmsignalisactivatedwhentheinsulationresistancevaluedropsbelow50kΩ.

Instrument:rheostat.

56afterdisconnectingtheloads,eachconductorofthecircuitpoweredbythesecondaryoftheinsulatingtransformerisconnected-oneatatime-withtheequipotentialnodeusingtherheostat (fig.4.4).Faultsimulation is implementedbyreducingtheresistanceof therheostattoavalueR<50kΩ.Thismustcausetheopticalandacousticalarmsystemtotrip.Then,byincreasingRuptovalueshigherthan50kΩ,youcancheckthatthealarmcanbedeactivatedautomatically.

230 V/50 Hz


network

insulation monitoring device



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Figure 4.5: Measurement of the leakage currents of the insulating

transformer

4.2.1continued

Functional test of signalling systems

Purpose of the test:tocheckthattheopticalandacousticalarmsystemsarefunctioning.

56thetestisperformedbyassessing,bymeansofavisualinspection,thatthefollowingprescriptionshavebeenrespected:- presenceofthesignallingindicatorlight,litupgreen,indicatingnormaloperation;- presenceofthesignallingindicatorlight,litupyellow,whichcomesonwhenthealarm

deviceintervenes(insulationresistance<50kΩ);- impossibilityofswitchingoff theyellow indicator light; itmustswitchoffonlyafter the

signalledfaulthasbeeneliminated;- presenceofanacousticsignalthatstartstofunctionwhenthealarmdeviceistripped

(insulationresistance<50kΩ);thesignalmustbeaudibleintheroomsofthedepartmentwheremedicalpersonnelareexpectedtobepresent.

Measurement of the leakage currents of the insulating transformer

Purpose of the test:Tocheckthattheearthleakagecurrentofthesecondarywindingandthecasingoftheinsulationtransformerisnothigherthan0.5mA.

Instrument:milliammeter.

Procedure:a)earthleakageofthesecondarywindingismeasuredwiththetransformerpoweredwith

noloadattheratedvoltage,withtheinsulationmonitoringdevicedeactivatedandbyconnecting the milliammeter between the equipotential node and each pole of thetransformeroneatatime(fig.4.5).

b)theearthleakageonthecasingismeasuredontheaccessiblemetalpartsthatarenotconnected to earth (for example, rivets, screws etc.), and on the insulating parts byapplyingametalsheetonthese.

230 V/50 Hz

I 0.5 mA


network

insulation monitoring device (disconnected)



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Measurement of the supplementary equipotential connections (group 2 medical locations)In group 2 medical locations the resistance of each conductor for connection to theequipotentialbondingbusbarmustbemeasured.

Purpose of the test:tocheckthateachconnectionbetweentheequipotentialnodeandtheearthoftheplugsockets,theearthterminaloffixeduserdevicesandanyextraneousconductiveparthasaresistancenohigherthan0.2Ω.

Instrument:fourterminalswitchgear,workingaccordingtothevolt-ammetricprinciple,withano-loadvoltagebetween4and24Vina.c.ord.c.andcapableofprovidingacurrentofatleast10A.

Procedure:theterminalsoftheinstrumentareconnectedononesidetotheequipotentialbondingbusbarandontheothertotheconductivepartorextraneousconductivepart,asindicated in figure 4.6. The test current is circulated by means of the ammetric circuit(terminalsA1andA2)whilevoltageismeasuredbymeansofthevolumetriccircuit(terminalsV1andV2).Thepinsmustbe locatedat twodifferentpoints,bothontheequipotentialbondingbusbarandontheconductivepart.InthiswayitispossibletomeasurenotjusttheresistanceRcoftheequipotentialconductor,butalsothecontactresistancesoftheconnections of the conductor itself (R1 and R2). In the presence of a subnode, themeasurement must be performed between the equipotential bonding bus bar and theconductivepartorextraneousconductivepart;inotherwords,itmustsimultaneouslyinvolvebothconductors-theonebetweentheequipotentialnodeandthesub-nodeandtheonethatconnectsthesub-nodetotheconductivepartorextraneousconductivepart(fig.4.7).

V1

V2A1

A2

B

RcR1 R2

V

A B

R1R2

Rc

Strumentodi misura

Sub-nodo

Conduttoreequipotenziale

Massa estranea

Nodo principale

A

AG

V1

V2

A1

A2

B

RcR1 R2

V

A B

R1R2

Rc

Measuring instrument

Sub-node

Equipotential conductor

Extraneous conductive part

Main node

A

AG

4.2.1continued

Figure 4.6: Measurement of the resistance of supplementary equipotential conductors.

Figure 4.7: Measurement of the equipotential connection of an extraneous conductive part through a sub-node.


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4.2.1continued

Testing supplementary equipotential connections (group 1 medical locations)Thetestisperformedbymakingsurethattheconnectionsoftheprotectionandequipotentialconductorsandoftheequipotentialbondingbusbararemadecorrectlyandthattheyareintact.

Purpose of the test:tochecktheelectricalcontinuityoftheconductors,inotherwordsthattherearenofalsecontacts(withoutmeasuringtheirresistance).

Instrument:ohmmeterwithano-loadvoltagebetween4and24VinACorDCandthatsuppliesacurrentofatleast0.2A.

Procedure:theterminalsoftheinstrumentareconnectedononesidetotheequipotentialbondingbusbarandontheothertotheconductivepartorextraneousconductivepart,thenacheckismadetoensurethatthecurrentsuppliedfromtheinstrumentdoesnotdropbelow0.2A.

Measurement for the identification of extraneous conductive parts

Purpose of the test:toassesswhetherametalpartisanextraneousconductivepartbymeasuringresistancetoearth.Itisconsideredtobeanextraneousconductivepartiftheresistancevaluemeasuredislessthan0.5MΩingroup2medicallocationsandlessthan200Ωinthegroup1medicallocations.

Instrument:ohmmeterorappropriatetoolequippedwithaplugsockettobeinsertedinasocketofthesystemandwithasensortobeplacedincontactwiththepossibleextraneousconductivepart.

Procedure:themeasurementistakenbyconnectingoneofthepinsoftheinstrumenttothe equipotential bonding bus bar and the other on the metallic structure in question(fig.4.8).

operatingroomequipotential

bonding bus bar

if R < 0.5 MΩ

the structure is a extraneous conductive part

Visual inspectionThevisualinspectionmustaddressthefollowingaspectsinparticular:-coordinationofprotectiondevicesinTNandTTsystems;-calibrationoftheprotectiondevices.-characteristicsofSELVandPELVsystems;-firesafetydevices;-circuitconfigurationsforsupplyingpowertoplugsocketsingroup2medicallocations;-identificationoftheplugsocketssuppliedbysafetysources;-performanceofthesourcesanddevicesforsafetypowersupplyandlighting.

Figure 4.8: Measurement of the earth resistance of

extraneous conductive parts.


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4.2.2

Periodic inspectionsIn addition to detailed and precise prior maintenance, the medical locations also needperiodicchecksatspecifictimeintervals.Thepurposeoftheperiodicchecksistoensurethattheconditionsofacceptabilityandstandardscompliancethatwerefoundduringtheinitialchecksaremaintained,aswellastomakesureofthecorrectoperationofthesafetydevicesandsystems.Table4.1summarisesthecheckstobecarriedoutontheelectricalsystemsofmedicallocations,andthecorrespondingfrequencyrequiredbyIEC60364-7-710.Itisimportantto note that these checks are in addition to those required by IEC 60364 for ordinarysystems.

Check Frequency

1 Functionaltestoftheinsulationmonitoringdevices(onMedicalITsystems)

6months

2 Check,bymeansofavisualinspection,ofthecalibrationofadjustableprotectiondevices

1year

3 Measurementsoftheresistanceofsupplementaryequipotentialconnections

3years

4 TestthattheRCDsinterveneatthevalueofIdn 1year

5 Functionaltestofthepowersupplytosafetyserviceswithcombustionengines:•no-loadtest•testwithload(foratleast30minutes)

1month4months

6 Functionaltestofthepowersupplyofbattery-poweredsafetyservices,inaccordancewiththemanufacturer’sinstructions

6months

4.2.3

Recording of the resultsThedatesandtheresultsofbothinitialandperiodictestsmustberecordedonpaperorelectronic media and conserved over time, as required by article 710.6 of the IEC60364-7-710.

Table 4.1: Periodic checks that must be carried out on the electrical systems of group 1 and group 2 medical locations.


Appendix

5.1

Logical path for the design of electrical systems in premises for medical use

Declaration of the healthcare manager on the type of healthcare operations that will be carried out in the medical locations

Definition of the type of medical location

Analysis of the risks deriving from electromagnetic fields, atmospheric discharges, overvoltage on the power supply, fire

Identification of the air conditioning ducts of the premises, and of the piping for medical gases or anything else

Identification of the patient environment

Determination by the healthcare manager of the electromedical devices that will be used in the room and the corresponding power absorption values

Subdivision of the electromedical devices between ordinary devices and devices that must be powered by an Medical IT system

Definition of the size of the insulating transformer according to the power of the equipment envisaged in the room

Identification of the conductive parts and extraneous conductive parts that must be connected to the equipotential node

Identification of the duct paths and the positions where the switchboards and the equipotential node are to be located as well as the spaces

required for maintenance

Identification of specific requirements or restrictions and of the possible need for screens against external electromagnetic fields

Sizing of the conductors and the protections

Choice of operating and protection equipment


5

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5.2

Options for design Thedesignofahospitalelectricalsystemrequiresacarefulappraisalofnumerousfactorsthat togetherguaranteeacorrectsynthesisbetween two intrinsicallyantitheticaspects:protectionandoperational continuity.Thehospitalelectricalsystemforgroup2medicallocationshasahighdegreeofcomplexityandmusttakeaccountofcoordinationwiththedistributionupstream.Itistheprecisetaskof thedesigner toweighupthepossibledesignchoicescompatiblywith theapplicablestandardsandatthesametimewiththetechnicalrequirements.

Asasupport,anumberofalternativetypesofinstallationsthatthedesignermayhavetoevaluate are outlined below, with the intention of illustrating the advantages anddisadvantagesofthevarioussolutionsand,wherepossible,toofferaqualitativesuggestion.

Concentration of loads under a privileged line or separation of the privileged line from the UPS line.

ItisadvisedtodivideupthecircuitsasspecifiedbyIEC60364-7-710sothattherewillinanycasebeadualpowersupplyonthecircuitsoftheoperatingroom,evenwhenthepowerabsorbedbythenonMedical IT loadscanbeconsideredasnegligible inrelationtotheinstalledpower.

Concentration Division•Lesscomplexityofthesystem•Lowercosts•NouseoftheRCDprotectingthe

dedicatedlinesforthelightingsystemandmachinerywithpowerconsumption>5kVA,suchas,forexample,radiologicaldevices

•NoselectivityonthesecondaryUPS

•Redundancyofthecircuits•Continuityofservice:iftheRXdoesnot

function,thelinesoftheemergencysectionoperatenormallyinanycase

•Reductionofthepowerconsumptionofthemedicalinsulatingtransformer

•ReductionofthesizeoftheprotectiondevicesinsidetheMedicalITboard


Ordinaryloads

Privilegedloads

Lightingsystem

MedicalIT loads

operating theatre


Ordinaryloads

Privilegedloads

Lightingsystem

MedicalIT loads

operating theatre


5

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Thechoiceofthemostsuitableprotectiondevicedependsontheapplicationcontextandmustbeprescribedbythedesigner.Inintensivetherapypremises,inwhichthepatientshave an extended stay in hospital, it is advisable to service the loads with multipletransformers,both to increasecontinuityofserviceand inorder tobeable tocarryoutmaintenanceoperations,whichmustnotcausedisturbancetothepatients.Inthesurgicaloutpatientdepartments,ontheotherhand,itmaybeappropriatetodistributethepowersupplyfromasingletransformer,becausetheamountsofpowerabsorbedaregenerallyverylimitedanditispossibletomanageapowerreservealsowitha3or5kVAinsulating transformer. In these rooms,however, there isvery limitedspace inwhich topositiontheswitchboard,andthereforeitmaybepreferabletopreferaswitchboardwithsmalldimensions.

Concentration or distribution of power in group 2 medical locations

Concentration Distribution•Reductioninthenumberofswitchboards•Reductionofdimensions•Poweravailableforfutureexpansionsof

thesystem•Lowercosts

•Redundancy•Greatercontinuityofservice•Easeofmaintenance•Quickerfaultfinding•Reductionofthedimensionsofthe

individualswitchboard•Easiertoinstallwall-mounted

switchboard

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Socketunit

Thechoiceofthemostsuitableprotectiondevicedependsontheapplicationcontextandmustbeevaluatedbythedesignertakingaccountoftheaboveconsiderations.

Protection of Medical IT circuits by means of fuses or miniature circuit breakers

Fuses Miniature circuit breakers•Highbreakingcapacity•Speedofactivation•Selectivitywiththesocketunitson

shelves,headboardandcontrolpanelsoftheroom

•Betterhorizontalandverticalselectivityofthecircuits

•Replacementofthedamagedpartonly•Thedeviceisnotaffectedbythe

malfunctionsincethedamagedcartridgehasbeenreplaced

•PossibilitytosectionthelinewithaloadbymeansofadevicewithanAC-22Busagecategory

•Instantaneousrearming•Speedofmaintenance:noneedto

replacetheactiveparts•Nospecialskillsrequiredformaintenance•Calibrationoftheprotectiondevice

cannotbealteredbytheuserthroughreplacementofcomponents

•Possibilityofinstallingnumerousaccessoriesincludingsignalcontacts

5.2continued


5

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Itisstronglyrecommendedtoprotectthepowerlineoftheinsulationmonitoringdevicebymeansofanappropriatelycoordinatedfuseblockbase.ToavoiddeactivationoftheinsulationmonitoringdevicewhiletheIT-Mcircuitisfunctioning,itisadvisabletoinstallthefuseblockinaninaccessiblepartoftheswitchboard,typicallyonthebackofswitchboarddoor.Forthesamereason,itisimportantthatthefuseblockbaseisnotsubjecttosectioningandislead-sealedintheclosedposition:inthiswayitisguaranteedthatthepowersupplyoftheinsulationmonitoringdevicecanonlybecutoffwhenthetransformersecondary,andthereforetheoperatingroom,isnotinoperation.

Protection of the insulation monitoring deviceing device against short circuit and overload

Protect Do not protect•Possibleoverloadsandshortcircuitsare

avoided•Breakageoftheinsulationmonitoring

deviceisavoided•Fireprinciplesareavoidedinsidethe

switchboard•OperationalcontinuitytotheMedicalIT

circuitsisguaranteed

•Costofprotectiondevices•Internaldimensionsoftheswitchboard•Riskofmakingtheprotectiondevice

ineffectiveifaninappropriatefuseisused•Riskofbreakageoftheinsulation

monitoringdeviceduetooverloadorcontainedshortcircuit

Auxiliarypower supply

Controlcircuit

Insulationmonitoring device


Controlcircuit



Controlcircuit



Controlcircuit


It is alwaysadvised touseanRCDonall nonMedical IT circuits:RCDs in fact enableprotectionagainstfirerisksandmakeitpossibletocontainamalfunctionwithintheaffectedcircuit,withoutcausingmoreseriousrepercussionstothesystemupstream.

Protection of non Medical IT circuits by means of a Residual Current Device (RCD)

RCD use No RCD•ByusinganRCDwithIdn=0.03A

additionalprotectionagainstdirectcontactsisalsoguaranteed

•ProtectionagainstfireriskswithIdn≤0.5A•Isolationofthemalfunctioninsidethe

circuitinvolved•SelectivecoordinationbetweenRCDs

•Nountimelytripping•Conformancetoprotectionagainst

indirectcontactsisguaranteed,inTNsystems,bythermomagneticswitches

•Essentialconfigurationofthesystem•Reductionofperiodicchecks•Selectivityonindirectcontactstobe

implementedbymeansofthermomagneticswitches

5.2continued


5

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5.3Leggi e decreti

Electromedical devices with applied parts

Thefollowingtableliststhepowerconsumptionvaluesofthemainelectromedicaldevicesinstalledinoperatingrooms.Ascanbeseen,theoverallpowerrequirediscloseto13kWandthisinvolvestheuseofatleasttwomedicalinsulatingtransformers.

Power installed in a heart surgery operating roomDefibrillator 320WInfusionpumps 50WDisplay 100WXenonlightsource 1500WElectroscalpelmonitor 1300WLocalpowersource(monitoring) 2500WBloodheatexchanger 2400WExtracorporealpumps 160WAirheatingforpatient-Thermacare 1400WN.3scialyticlamps 450WNegativoscope 200WTotal installed power 10380 WN.B.Powerconsumptionstobeconsideredwithasimultaneousexecutionfactorof1,asspecifiedbythestandard

5.4

Laws and decreesIEC, CENELEC standards

EN 50110-1Operationofelectricalinstallations

IEC 60947-2 Low-voltageswitchgearandcontrolgear-Part2:Circuit-breakers

IEC 61008-1Residual current operated circuit-breakers without integral overcurrent protection forhouseholdandsimilaruses(RCCBs)-Part1:Generalrules

IEC 60079-10-1Explosiveatmospheres-Part10-1:Classificationofareas-Explosivegasatmospheres

IEC 60598-1Luminaires-Part1:Generalrequirementsandtests

IEC 60598-2-22Luminaires-Part2-22:Particularrequirements-Luminairesforemergencylighting

IEC 60598-2-25Luminaires-Part2:Particularrequirements-Section25:Luminairesforuseinclinicalareasofhospitalsandhealthcarebuildings

IEC 60601-1Medicalelectricalequipment-Part1:Generalrequirementsforbasicsafetyandessentialperformance

IEC 60601-2-21Medicalelectricalequipment-Part2:Particularrequirementsforthesafetyofinfantradiantwarmers

IEC 60601-2-27Medical electrical equipment - Part 2: Particular requirements for the safety, includingessentialperformance,ofelectrocardiographicmonitoringequipment

IEC 60601-2-46Medicalelectricalequipment-Part2-46:Particularrequirementsforthesafetyofoperatingtables


5

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IEC 60601-2-41Medical electrical equipment - Part 2: Particular requirements for the safety of surgicalluminairesandluminairesfordiagnosis

IEC 364-4-444Electricalinstallationsofbuildings-Protectionagainstelectromagneticinterferences(EMI)ininstallationsofbuildings

IEC 60364Electricalinstallationsofbuildings-Part1:Scope,objectandfundamentalprinciples

IEC 62305-1Protectionagainstlightning.Part1:Generalprinciples

IEC 62305-2Protectionagainstlightning.Part2:Riskmanagement

IEC 62305-3Protectionagainstlightning:Part3:Physicaldamagetostructuresandlifehazards

IEC 62305-4Protectionagainstlightning:Part4:Electricalandelectronicsystemswithinstructures

IEC 61557-8Electricalsafetyinlowvoltagedistributionsystemsupto1000Va.c.and1500Vd.c.-Equipmentfortesting,measuringormonitoringofprotectivemeasures-Part8:InsulationmonitoringdevicesforITsystems

IEC 61558-1Safety of power transformers, power supplies, reactors and similar products - Part 1:Generalrequirementsandtests

IEC 61558-2-15Safety of power transformers, power supply units and similar - Part 2-15: Particularrequirementsforisolatingtransformersforthesupplyofmedicallocations

5.4.1

ISO, CEN standards

EN 737-3Systemsfordistributionofmedicalgases-Systemsforcompressedmedicalgasesandvacuum

EN 838Applicationsoflightingtechnology.Emergencylighting

ISO 11197Powersupplyunitsformedicaluse

EN 12464-1Lightandlightingsystems-Lightingintheworkplace-Part1:Internalworkplaces

5.4continued

H+

Lin

e P

ractical guide for group

2 med

ical locations H+LinePractical guide for group 2 medical locations

2CS

C47

0010

B02

01 -

07/

2010

Contacts

ABB SACEA division of ABB S.p.A.Modular DevicesViale dell’Industria, 1820010 Vittuone (MI) - ItalyTel.: +39 02 9034 1Fax: +39 02 9034 7609

bol.it.abb.comwww.abb.com

Data and images are not binding. Depending on technical development and the products, we reserve the right to modify the content of this document without notice.

Copyright 2010 ABB. All right reserved.

h+line practical guide for group 2 medical locations€¦ · 2.1.2 medical electrical equipment ......

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