separation distance

© 2012 DEHN + SÖHNE / protected by ISO 16016 1

Separation Distance

Separation Distance

© 2012 DEHN + SÖHNE / protected by ISO 16016 Separation Distance 2

Proximity between the telecommunication line and the down conductor

Telecommunication line


Faulty installationSeparation distance?

s?

s?


Separation distance sProblematic installation of metal lines

06.10.09 / S6047e

e.g. e.g. electric line

Ref.: IEC 62305-3:2006; Annex E, Figure E.38

s

l


Electrical insulation of the external LPS

IEC 62305-3:2006, 6.3

kcs = ki l

km

“The electrical insulation between the air-termination or the down-conductor and the structural metal parts, the metal installations and the internal systems can be achieved by providing a distance d between the parts greater than the separation distance s‘:

ki depends on the selected class of LPS (see Table 10);

kc depends on the lightning current flowing on the down conductors (see Table 11);

km depends on the electrical insulation material (see Table 12);

l is the length, in metres, along the air-termination or the down-conductor, from the point where the separation distance is to be considered, to the nearest equipotential bonding point.“


Insulation of the external LPSValues of coefficients ki and km

Ref.: IEC 62305-3:2006, 6.3, Table 10 + 12 *DEHNiso value stated by DEHN + SÖHNE (Dr. Zischank VAZ)

Class of LPS ki

Material km

NOTE 1 When there are several insulating materials in series, it is good practice to use the lower value for km.NOTE 2 The use of other insulating materials is under consideration.

I 0.08II 0.06III and IV 0.04

Air 1Concrete, bricks 0.5DEHNiso* spacer / Combi 0.7


Separation distanceCoefficient kc for an air-termination rod

S

Individual air-termination rod

kc = 1

Ref.: IEC 62305-3:2006, Annex C, Figure C.1


Formulas for the calculation of the partitioning coefficient kc

Formula for the calculation of the partitioning coefficient kc in case of two down conductors and a type B earth-termination system

h + ckc = ————

2h + c

1 ckc = + 0,1 + 0,2 2 n h

3

Basic formula for the calculation of the partitioning coefficient kc

Legend:n Total number of down conductorsc Distance of a down conductor to the next down conductorh Spacing (or height) between ring conductors

Ref.: IEC 62305-3:2006, Annex C, Figure C.2


Formulas for the calculation of the partitioning coefficient kc

From the point of proximity to the 1st node kc1 = 1

From the 1st node to the next node• in case of two outgoing lines kc2 = 0.5 • in case of three outgoing lines kc2 = 0.33 • in case of four outgoing lines kc2 = 0.25

National specification for the partitioning coefficient kc

for buildings with “meshed“ air-termination system

Every further node reduces the kc value* by half

* NOTE: The value should not be smaller than 1n


Calculation example of the separation distance sBuilding with gable roof, class of LPS III

Calculation according to IEC 62305-3

Number of down conductors: 4

8 m

c = 14 m

l = 12 m 1 ckc = + 0.1 + 0.2 2 n h

3h = 6 m


Calculation of kc according to IEC 62305-3


1 ckc = + 0.1 + 0.2 2 n h

3

1 3 14 kc = + 0.1 + 0.2 = 0.490

2 4 6

n = 4 Total number of

down conductors

h = 6 m Height or spacing

of the ring conductors, gutter

c = 14 m Max. distance between two down conductors



kcs = ki l (m)km

s = 0.04 12 m = 0.47 m0.490

0.5

Coefficient class of LPS III: ki = 0.04

Partitioning coefficient: kc = 0.490

Material used for the isolating distance Brick: km = 0.5

Length along the air-termination conductor / down conductor: l = 12 m

Calculation of s according to IEC 62305-3



Calculation of s according to IEC 62305-3

Number of down conductors: 4

8 m 14 m

s = 0.04 17 m = 0.66 m0.490

0.5l = 17 m

Lamp

•Lamp •Conductors•Heating •Water ...

© 2012 DEHN + SÖHNE / protected by ISO 16016 Separation Distance

Separation distance - Example 2.2 km = solid materialAir-term. rod connected twice to the mesh network

l=10m

Air-termination rod

Roof superstructure

s = ki (kc1 l1 + kc2 l2 + ... + kcn ln) / km =s = 0.06 (0,5 8m + 0.25 4m + 0.125 10m + 0.063 10m + 0.042 8m) / 0.5 =s = 0.87m for solid material

kc6=0.042l6 = 8 m

kc5=0.063l5 = 10 m

kc2= 0.5l2 = 8 m

kc3= 0.25l3 = 4 m

Roof superstructureh = 2m

20 m

kc4=0.125l4 = 10 m

kc2= 0.5l2 = 8 m

s

Class of LPS IIHeight of the building h / length l to the earth-termination system: l = 8m Mesh size: 10m x 10mNumber of down cond.: n = 24 Min. value for kc: = = 0.0421

n1

24


Separation Distance

Calculation according to Nodal Analysis


Nodal analysis - Software for the determination of the separation distance sEvery line is shown as a resistor.

The voltages of the nodes, i.e. the difference between the node potentials, are calculated by means of the supply of a defined lightning current and the mathematical solution of the equation.

= node

R14 R15 R16 R17

R6 R7 R8 R9 R10 R11 R12 R13

R2 R3 R4 R5

R1

I

0V 0V 0V 0V


Model for the determination of current division Nodal analysis


DEHN Distance ToolStart software

Spearartion distance calculated according to

nodal analysis


DEHNconductorHVI® Conductor

TechnologyFields of Application


Basic development of a creepage discharge at the HVI conductor with special coating

Insulation, semiconducting

Inner conductor

EB connection via earthing clamp

Proximity to earthed metal parts

© 2012 DEHN + SÖHNE / protected by ISO 16016 HVI-Seminar HVI-Leitungen

External coating(weather and UV resistant)

Conductive shield(e.g. braided copper)

Field control

HV-Insulationconductor

Connection with the air termination

Induction of the lightning current(feeding point)

Coaxial Cables with Field Control andConductive Shield as insulated Down-conductors

© 2012 DEHN + SÖHNE / protected by ISO 16016 HVI-Seminar HVI-Leitungen 11.12.03 / 3465

Lit.:

connection toequipotential bonding

high-voltageresistant isolation

inner conductor

connection to the air-termination system

incoming lightningimpulse current

semi-conductivecoating

sealing unit area

Basic illustration of the structure of an isolated down conductor with semiconductive coating


DEHNconductor system, HVI® conductor I

Conductor length has to be specified

EB clamp Part No. 405 020

Conductor holder Part No. 275 120

Head piece

HVI conductor I Part No. 819 020

Fixed EB element

Earth connection element (removable)

Sealing end sectionEarth connection


Installation of the different types of HVI® conductors

HVI® conductor type I

EB connection

Sealing end

HVI® conductor type II

EB connection

HVI® conductor II,fixed length,secong sealing endfixed

Sealing end

HVI® conductor type III

HVI® conductor III,can be cut to length,second sealing endhas to be mounted

Sealing end

EB connection


Isolate air-termination system for mobile radio stations DEHNconductor system HVI® conductor

Source: Bischof-Blitzschutz, Weyhe

Air-termination tip

GRP supporting tube

No metal parts may be installed in the sealing end section!

HVI® conductor

EB element

Aluminium supporting tube


Grey HVI® conductor installed in the supporting tube with integrated sealing end and air-termination tip

HVI® conductor IIPart No. 819 324

HVI® conductor IPart No. 819 323

HVI® conductor IIIPart No. 819 325

GRP supporting tube

HVI conductor

Air-termination rod

Aluminium supportingtube


Cable duct

Cable duct

Foundation earth electrode

Isolated air-termination system

Metal roof superstructure

Reinforcement

Voltage-controlled insulated down conductorSeparation distance is maintained

a

Sealing end metal capping of the parapet locatedin the protection area of an isolated air-termination system is connected to equipotential bonding

Insulated HVI® conductor I

Equipotential bondingconnection

Equivalent separation distanceof the HVI conductor:s = 0.75 m in airs = 1.50 m for solid material

Separation distance s


Isolated Lightning Protection

Air-Termination Masts and HVI Conductor Light


DEHNconductor system / HVI® conductor light

Disposable reel made of plywood(Ø approx. 80 cm), width approx. 50 cmTotal weight approx. 66 kg

HVI conductor light

Prerequisite for the use of HVI conductors light: Separation distance 0.45 m (in air)

Length 100 m on a reel: Part No. 819 125

Equiv. separ. distance s 0.45 m (in air) 0.90 m (solid material)

Core Copper (soft)Cross-section 19 mm²Insulation PE (polyethylene)Outer diameter 20 mm

(black sheath 17 mm)Colour Dark grey


Isolated lightning protection systemHVIÒ conductor light, class of LPS III

Detail Aair-termination mast HVI conductor light

30 m

18.1

m

Detail Aair-terminat-ion mast

15 m


1.90 m

27 m

Protection area Protection area

Protection areaProtection area

20 m

Isolated lightning protection systemHVIÒ conductor light, class of LPS III

HVI conductor light

1.5 m

30 m

1.5 m


DEHNconductor system / HVI® conductor light Isolated air-termination system, air-termination mast

SET I Air-termination tip 1000 mm

total height 2900 mm,with

supporting tubeand tripod

Air-t

erm

. tip

1mNo electrically

conductive or earthed parts may be located in this protection area!

s a

djus

tmen

t ran

ge a

ppro

x. 1

40 c

m


DEHNconductor system / HVI® conductor light Isolated air-termination system, flat roof

SET II Air-termination rod 2000 mm

total height 3900 mm,with

supporting tubeand tripod

Air-t

erm

. rod

2m


DEHNconductor system / HVI® conductor light Isolated air-termination system, flat roof

Connecting plate with 4 connection possibilities

separation distance

Documents

dehn shne

separation distance

separation distanceformulas

separation distanceinsulation

distance d

outgoing lines kc2

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