Bebco Purge Guide

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<p>PROCESS AUTOMATION</p> <p>BEBCO EPS PURGE/PRESSURIZATION SYSTEMS ENGINEERS GUIDE</p> <p>SPOTLIGHT on PURGE/PRESSURIZATION SYSTEMSP+F Bebco EPS The international-compliant purge &amp; pressurization systemPurge &amp; pressurization protection is suitable for many applications and is one of the most exible Ex protection solutions. This ignition protection class makes it possible to operate non-Ex-capable devices in hazardous areas rated Zone 1/Division 1 and Zone 2/Division 2.</p> <p>The 6000 Series Type X, Ex px certied IP65/Type 4X stainless steel housing facilitates user-friendly, menu-driven conguration Can be used worldwide in Class I/II, Division 1, and Zone 1 / Zone 21 hazardous areas in safety applications up to SIL 2 with SIL 3 option Based on a universal mount design allowing the control unit and vent to be located virtually anywhere on or in the protected enclosure</p> <p>The 3000 Series</p> <p>N</p> <p>EW</p> <p>Enviro-LineThe Enviro-Line series of environmental pressurization systems is suitable for nonhazardous areas that contain dusty, dirty, and corrosive atmospheres.</p> <p> Type Y/Z and Ex py/pz certied Features a gas manifold block that reduces panel size Allows operation of non-Ex-capable equipment in Division 2 and Zone 2 areas Panel or component kit available</p> <p>The 1000 &amp; 2000 SeriesType X, Y, Z 1000 and 2000 purging systems have provided a dependable solution for hazardous area protection for many years. Their proven track record of superior performance, along with our worldwide support, has resulted in a high level of satisfaction.</p> <p>Visit us at www.pepperl-fuchs.com</p> <p>Table of ContentsIntroduction................................................................................... 1 Type.Y.and.Z.Systems.(1000.Series)............................................25 . Type.Z.Systems.(1000.Series). .................................................... 41 Type.Y,.Z.and.Ex.[nP].Systems.(3000.Series)...............................45 Type.X.Systems.(2000.Series).....................................................63 Type.X.and.Ex.[px].Systems.(6000.Series)..................................91 Enviro-Line................................................................................ 103 Custom.Cabinet.Solutions......................................................... 105 Accessories. ...............................................................................111 .</p> <p>Defining the Need Theneedtoplacegeneral-purposeequipmentinhazardous (classified)locationsisnotnew,yetinthelastthreedecades theneedhasintensifieddramatically.Thisisprimarilydueto thefollowingfacts: Processcontrol,measuringandrecordingequipmentthat was once primarily pneumatic is now primarily generalpurposeelectronicequipment. Motors and switchgears now use electronic accessories tosatisfytheneedsforposition,speedorprocesscontrol andenergyefficiency,whichoftenrenderstheequipment unsuitableforuseinhazardouslocations. Newlydevelopedequipment,suchasroboticmanipulators, CNCs, batch weigh/count and filling systems, analyzers, programmable controllers and CRT work stations are rapidly becoming more prevalent in the industrial work environment. While the demand for these new devices continues to grow, most of them cannot be economically installed in a hazardous location by using explosionproof enclosures or intrinsic safety barriers, alone. Most modern electronic equipment is expensive and delicate. For this reason, it requires environmental protection that cannot be provided byexplosionproofenclosuresorintrinsicsafetybarriers. Therefore, the need for an alternative to explosionproof enclosuresandintrinsicsafetybarriershasbecomeextremely critical. A Pepperl+Fuchs Rapid ExchangeTM Purging System and several accessories make this enclosure acceptable for Class I, Group C &amp; D, Division 2 hazardous locations.</p> <p>The alternative is purge and pressurization. Asyoulearnmoreaboutpurgeandpressurization,itwill become apparent that this technology is exactly what you require. It will then become obvious that this technology offers the safest and most economical means of installing electricalequipmentinahazardouslocation.Inaddition,this technologywillundoubtedlyimpressyouastheonlydefinitive waytoenhanceyourequipment'sperformanceandaccess, whileincreasingthelifeexpectancyofdelicateinstruments. Finally,you'lllearnthemostimportantpointofall:</p> <p>The answer to your need is Pepperl+Fuchs.</p> <p>Purge/Pressurization Systems technology review</p> <p>Examining the SolutionsIntroductIonExplosionproof EnclosuresIntent Theseenclosuresaredesignedtocontainanexplosionifan electricaldeviceignitesflammablesubstanceswithintheenclosure, thuspreventingignitionofthesurroundingatmosphere.These enclosuresarecommonlyusedforcircuitbreakers,mechanical switchgearsandhigh-poweredequipment.Thefailuretoproperly tighten all bolts and screw covers on these enclosures is the greatestproblemfacingendusers.</p> <p>Advantages ExplosionContainment RequiresLowMaintenance High-PoweredEquipment NoElectronics NoMovingParts</p> <p>Disadvantages CannotIndicateFailureofContainmentCapability DangertoEquipmentAfterExplosions PossibilityofInstallation/MaintenanceErrors CostofProtectionperft3IncreasesWithEnclosureSize WindowsareLimited PromotesCondensation LimitedSizes Cumbersome,LimitedAccess BulkyDesigns CausesHarmfulHeatBuildup ExcessiveWeight</p> <p>Intrinsic Safety Barriers</p> <p>Intent Thesedevicesaredesignedtolimitthecurrentandvoltage conductedthroughadevice'spowerorsignalwiring.This limitationpreventsshortingandarcingofthewiresordevice, thus preventing ignition of the surrounding atmosphere. Theyarecommonlyusedforprotectionofinstrumentsthat operateatextremelylowpowerlevelsandaresuitablefor exposuretotheenvironment.</p> <p>AdvantagesTheOnlyProtectionAllowedforZone0 EliminatesPossibilityofExplosion NoHotPermits RequiresLowMaintenance NoSpecialCables IdealforLow-PowerDevices LimitsEnergytoDevice</p> <p>DisadvantagesRequiresDocumentationofI.S.CircuitsandInstallation CanbeUsedOnlyWithLow-PowerDevices</p> <p>Pepperl+Fuchs Group www.pepperl-fuchs.com</p> <p>Germany: +49 621 776 2222 pa-info@de.pepperl-fuchs.com</p> <p>USA: 330 486 0002 pa-info@us.pepperl-fuchs.com</p> <p>Singapore: +65 67799091 pa-info@sg.pepperl-fuchs.com</p> <p>Purge/Pressurization Systems technology review</p> <p>Pepperl+FuchsIntroductIonEnclosure Protection SystemsIntent Pepperl+Fuchsproductsaredesignedtosupplyoneor moreprotectedenclosureswithcleaninstrumentairorinert gas. This process removes flammable gases or prevents the accumulation of ignitable dusts within the protected enclosure(s).Thismethodofprotectionisnotlimitedbythe quantity,configuration,powerrequirements,orlocationof the protected equipment. These systems are commonly usedforallapplicationsinvolvingbasicelectronics,electrical equipment,motorsandswitchgear. Inaddition,thesesystemscanalsomeetthedemandsof rackmountedinstrumentation,videodisplays,programmable controllers, computers, printers, recorders, measurement devices,gasanalyzersandcalibrationequipment. Oneofthebestbenefitsistheslowbutcontinuousflow ofprotectivegas,whichcanbespecificallyusedtoeliminate problemslikeheat,moisture,dustandcorrosion.Andunlike explosionproofenclosures,failureofaPepperl+FuchsBebco EnclosureProtectionSystemdoesnotcreateanimmediate danger.</p> <p>Advantages ReducesHeatBuildup InhibitsMetalCorrosion RequiresLowMaintenance IncreasesEquipmentLongevity NoSpecialEnclosuresRequired AllowsFastAccesstoEquipment ReducesMoisture&amp;DustBuildup ReducesClassificationWithintheEnclosure ContinuousSystemStatusIndication ProtectsEnclosuresupto450ft3 AllowsuseofanyEnclosureShape CostofProtectionperft3Decreases WithEnclosureSize</p> <p>Disadvantages ContainsMovingParts RequiresInstrumentAirSupply SomeSystemsRequireElectronics HotPermitsRequired</p> <p>Purge and Pressurization is the only technology that meets the demand for general-purpose equipment with standard enclosures inside hazardous locations</p> <p>Pepperl+Fuchs Group www.pepperl-fuchs.com</p> <p>Germany: +49 621 776 2222 pa-info@de.pepperl-fuchs.com</p> <p>USA: 330 486 0002 pa-info@us.pepperl-fuchs.com</p> <p>Singapore: +65 67799091 pa-info@sg.pepperl-fuchs.com</p> <p>Purge/Pressurization Systems technology review</p> <p>Defining Hazardous AreasClass RatingsClassesareusedtodefinetheexplosiveorignitable substancesthatarepresentintheatmosphere. class I - Flammablegasesorliquidvapors class II - Ignitablemetal,carbonororganicdusts class III - Ignitablefibrousmaterials</p> <p>Group Ratings</p> <p>Study guIde</p> <p>Groupsareusedtodefinesubstancesbyratingtheir explosiveorignitablenature,inrelationtootherknown substances. tyPIcAL cLASS I SuBStAnceS group A - Acetylene group B - Hydrogenor&gt;30%HydrogenbyVolume group c - EthylEther&amp;Ethylene Today's modern refineries and manufacturing complexes often contain both flammable gases and ignitable dusts, making area classification of Division 1 and Division 2 locations an important but tricky task. group d - Acetone,Ammonia,Benzene&amp;Gasoline tyPIcAL cLASS II SuBStAnceS group e - Aluminum,Magnesium&amp;Alloys group F - Carbon,Coke&amp;Coal group g - Flour,Grain,Wood,Plastic&amp;Chemicals</p> <p>Hazardous Area Definition Hazardous (classified) locations are those areas in an industrial complex where the atmosphere contains flammableconcentrationsofgasesorvaporsbyleakage, orignitableconcentrationsofdustsorfibersbysuspension ordispersion.</p> <p>Division RatingsDivisionsareusedtodefinethedegreeofhazardby determiningtheexplosiveorignitablesubstance's expectedconcentrationintheatmosphere. division 1 - Containssubstancesunder normalconditions division - Containssubstancesunder abnormalconditions</p> <p>The National Fire Protection Association TheNationalFireProtectionAssociation(NFPA),formed in 1896, is a nonprofit organization devoted to fire safety standards and codes. It currently retains over 40,000 memberswhoworktodeterminesafepracticesandestablish standardsforallareasofcommercial,industrialandresidential construction.TheypublishmanydocumentsincludingNFPA 70-betterknownastheNationalElectricCodeandNFPA 496-thedocumentthatspecifiesrecommendedpractices forpressurizationandpurging.</p> <p>Zone RatingsZonesareusedtodefinethedegreeofhazardby determiningtheexplosiveorignitablesubstance's expectedconcentrationintheatmosphere. Zone 0 - Containssubstancesunder normalconditions(Continuously) Zone 1 - Containssubstancesunder normalconditions(Intermittently) Zone - Containssubstancesunder abnormalconditions</p> <p>Area Classification Methods The NFPA establishes area classifications using three factors.IdentifiedasClasses,GroupsandDivisions,these factorsarecombinedtodefineconditionsofspecificareas.</p> <p>division 1 areas must be surrounded by division areas.</p> <p>Important notes:</p> <p>Pepperl+Fuchs Group www.pepperl-fuchs.com</p> <p>Germany: +49 621 776 2222 pa-info@de.pepperl-fuchs.com</p> <p>USA: 330 486 0002 pa-info@us.pepperl-fuchs.com</p> <p>Singapore: +65 67799091 pa-info@sg.pepperl-fuchs.com</p> <p>Purge/Pressurization Systems technology review</p> <p>Common Questions ?What is purging? Purgingistheprocessofsupplyingenclosureswithcompressed airorinertgasattheproperflowandpressureinordertoreducethe hazardousgasinsidetheenclosuretoasafelevel.Pressurization istheprocessofbringingcompressedairorinertgaswithinan enclosuretoapressurewherethereisnoingressofhazardousgasses orcombustiblegas.Bothpurgingandpressurizationarerequiredina ClassI,gasatmosphere.OnlypressurizationisrequiredinaClassII, dustatmosphere.</p> <p>How can the equipment be accessed? Equipmentmountedintheprotectedenclosurecan beaccessediftheareaisknowntobenonhazardous, orifallpowertotheprotectedequipmenthasbeendeenergized. In other words, internal equipment should betreatedasiflocatedinanexplosionproofenclosure. However, a cooling period may be required before accessing hot components, such as transformers or variable speed drives, which would otherwise be unacceptableforuseinthehazardouslocation. Equipment mounted through the surface of a protectedenclosuremayrequireasealedaccessdoor if the equipment is not suitable for exposure to the surrounding atmosphere. Advanced pressurization systems,likePepperl+FuchsBebcoRapidExchangeTM PurgingSystemscanmaintainapositivepressure,by increasingtheflowofprotectivegaswhiletheaccess doorisopen.</p> <p>What is used to purge/pressurize? Themostcommonandpracticalprotectivegasiscompressed instrumentqualityairthatcontainsnomorethantraceamounts ofcombustiblevapor.Inertgases,suchasnitrogenorargonare acceptable.Althoughtheyareusuallyexpensiveandimpractical, theymayberequiredforsomegasanalysisapplications.</p> <p>Study guIde</p> <p>What is the pressure requirement? Mostpurgingapplicationsrequireaminimumenclosurepressure of0.10inches(2.5mm)ofwater.Onepsiisequalto27.7inches ofwater.Insomecircumstances,aminimumenclosurepressure of0.50inches(12.7mm)ofwaterisrequiredtoprotectagainst ignitable dust. But in all cases, a higher enclosure pressure shouldbemaintainedtocreateareasonablesafetyfactor.Inrare circumstances,enclosurepressuresashighas2.5inches(63.5mm) ofwatermayberequiredtooffsetsuddenatmosphericpressure fluctuations, such as those created near missile launching or off-shoredrillingplatforms.</p> <p>How much purging gas is used? Averageprotectivegasconsumptionduringpressurizationata0.10 inch(2.5mm)enclosurepressureshouldfallsomewherebetween0.1 to3.5SCFHpercubicfoot(2.83to99.11l/hr)ofenclosurevolume. However,usewilldependontheprotectedenclosure'sintegrityand normalpressuresetting.Useisalsodependentonthequantityand sizeofcoversanddoorsaswellasdeviceswhichpenetratethe surface.Advancedformsofprotectionsuchascoolingordilution may require continuous flow rates of 30 to 100 SCFH (849.38 to 2831.26 l/m). Purging requires a much higher flow rate than pressurization,butonlyforashortperiodoftime.</p> <p>What kinds of enclosures can be purged? Anyenclosurecanbepurged,butenclosuresfeaturinggasketing andmultipledoorfastenersareideal.Therefore,intheabsence of official construction requirements for purged enclosures, Pepperl+Fuchs Bebco recommends enclosures which meet or exceedtheNationalElectricalManufacturersAssociationrating of NEMA 4 or NEMA 12. For more information on this subject, seepageT12.</p> <p>What kinds of devices can be purged? Virtuallyanybasicelectricaldevicecanbepurged,ifall"live" orenergizedcomponentscanbeisolatedfromthesurrounding environment. Devices such as pushbuttons, relays, timers and programmable controllers only need to be installed in a sealed enclosure.Motorsonlyrequireatotallyenclosedhousing.</p> <p>In this application, a stainless steel enclosure features an access door for control adjustments and maintenance, along with a very unique audible and visual alarm system.</p> <p>Pepperl+Fuchs Group www.pepperl-fuchs.com</p> <p>Germany: +49 621 776 2222 pa-info@de.pepperl-fuchs.com</p> <p>USA: 330 486 0002 pa-info@us.pepperl-fuchs.com</p> <p>Singapore: +65 67799091 pa-info@sg.pepperl-fuchs.com</p> <p>Purge/Pressurization Systems technology review</p> <p>NFPA &amp; ISA Design StandardsPressurization Standards Committee SP12 of the Instrument Society of America (ISA)establishedthefirstDesignStandardin1966,entitled "ISAs12...</p>