HIGH LOOP IMPEDANCE?

[WHY]

high earth loop impedence 1.42 and r1 r2 128 on a lighting cicuit in a T.N.C.S installation,any suggestions how to get this down?PLEASE HELP

 

[RF Lighting]

What sort of OCPD supplies the circuit?

What is the Ze of the property?
What size cable is the circuit wired in?
What is the length of the circuit?



1.42 ohms is normally an acceptable reading for a lighting circuit.

 

[Spark123]

What is 128?
Max Ze on a TN-CS should be 0.35 ohms btw.

 

[Lectrician]

Sounds fairly normal to me.

 

[Spark123]

I am still confused as to what the OP is saying. Is Ze 1.42ohms and R1+R2 128ohms?

 

[RF Lighting]

Maybe 1.28 ohms for R1+R2, and a Zs of 1.42 ohms?

This would mean a Ze of roughly 0.14 ohms which sounds about right for a PME supply.

 

[WHY]

sorry if i didn t explaine propely gentelmen,it was 1.28 r1 r2 and1.42 for the e.l.i on a lighting cucuit wired in 1.5 on a 6amp breaker.i was lead 2 believe anything over 1.00 was a problem?

 

[WHY]

just 2 clarify for eleci its a pretty long lighting circuit and i d also like to say thank you for all your replies

 

[dingbat]

sorry if i didn t explaine propely gentelmen,it was 1.28 r1 r2 and1.42 for the e.l.i on a lighting cucuit wired in 1.5 on a 6amp breaker.i was lead 2 believe anything over 1.00 was a problem?

If (R1 + R2) is 1.2 then that implies a circuit length of 42 metres, which is well within even the OSGs quite restrictive table of conventional circuits.

Given the Zs max for a 6A Type B MCB is 8.0, corrected to 6.4 Ohms, then at 1.42 you are well within the limits.