200v on the earth conductor of my lighting circuit

[spark-ticus]

Hi folks, I have put a new light circuit in a domestic property and am finding 200v on the earth conductor which is tripping rcd as soon as l switch the breaker on. With the circuit in question dead with all 3 cores out of the cu I test between L+E and N+E but am getting no continuity as soon as I power up the circuit though the voltage is there again. Any ideas where the voltage is coming from or how best to test for it would be greatly appreciated.

Thanks in advance guys an gals

 

[Stuuk1]

Earth been used as a switch wire or strapper?

Although you say you installed the lighting circuit...

The only other time I had something like this was on a large fan with flexi duct either side, the case was sitting at 150v!

 

[Benjamiin]

Had a fault find callout for the exact same thing, as odd as it sounds check your connections, we found a connector with feeds in was loose, the earth was carrying 230 to neutral and no voltage on lives, once we tightened the connector block we got voltage between live and neutral! Odd I know, but worth a go!!

 

[i=p/u]

Hmm reversed polarity do r2 test on all conductors using switches

 

[Octopus]

Hi folks, I have put a new light circuit in a domestic property and am finding 200v on the earth conductor which is tripping rcd as soon as l switch the breaker on. With the circuit in question dead with all 3 cores out of the cu I test between L+E and N+E but am getting no continuity as soon as I power up the circuit though the voltage is there again. Any ideas where the voltage is coming from or how best to test for it would be greatly appreciated.

Thanks in advance guys an gals

What did your dead tests show?? R1 + R2??

 

[Sparkyphill]

Have you took your supply from an existing circuit or from the CU, more info would be good

 

[Jdsparky]

Nail through cable tracking down to earth through building, usually capping nail catching live or neutral, had this before on a call out was fine for however long circuit was in for (I never put it in) then tripping Rcd occasionally and then all the time, when ir testing fault would come and go live earth.

 

[spark-ticus]

Took my supply straight from cu, have changed cu for new duel rcd board, down lights and ceiling roses are the light fittings

 

[Rockingit]

If you've downlights with drivers then it's not impossible (though unlikely) that one of them might be faulty or internally mis-wired, but my money would be on a cabling/connection issue somewhere and/or a polarity crossover.

 

[GLENNSPARK]

what you testing between conductors with?
low resistance ohmmeter or insulation resistance tester?

 

[HandySparks]

Hi folks, I have put a new light circuit in a domestic property and am finding 200v on the earth conductor which is tripping rcd as soon as l switch the breaker on. With the circuit in question dead with all 3 cores out of the cu I test between L+E and N+E but am getting no continuity as soon as I power up the circuit though the voltage is there again. Any ideas where the voltage is coming from or how best to test for it would be greatly appreciated.

Thanks in advance guys an gals

Which two points are you actually measuring this 200V between?

If the voltage is present only when you power up the circuit and then trips the RCD as soon as the breaker is switched on, how is the voltage present long enough for you to measure it?

 

[GLENNSPARK]

IR test it at 1000V between conductors on lighting circuit...

 

[Hawk81]

Have you tried to split the circuit down? To see if the fault is in the first half or second half. Simple things like this make it much easier to narrow a fault down

 

[Deleted member 9648]

Hi folks, I have put a new light circuit in a domestic property and am finding 200v on the earth conductor which is tripping rcd as soon as l switch the breaker on. With the circuit in question dead with all 3 cores out of the cu I test between L+E and N+E but am getting no continuity as soon as I power up the circuit though the voltage is there again. Any ideas where the voltage is coming from or how best to test for it would be greatly appreciated.

Thanks in advance guys an gals

Sorry but I'm struggling with this one.....you've obviously got an IR fault to earth and you are disconnecting the earth from the CU in order to power up in which case a voltage is going to appear on the now un-earthed earth wire.....and your checking continuity?

 

[MDJ]

Hi folks, I have put a new light circuit in a domestic property and am finding 200v on the earth conductor which is tripping rcd as soon as l switch the breaker on. With the circuit in question dead with all 3 cores out of the cu I test between L+E and N+E but am getting no continuity as soon as I power up the circuit though the voltage is there again. Any ideas where the voltage is coming from or how best to test for it would be greatly appreciated.

Thanks in advance guys an gals

Just carry out tests per normal on the newly installed circuit as your training, Dead tests first to confirm continuity of all cores and then R1&R2 tests, Polarity will then be confirmed before energising, never energise a circuit before testing, you may get a fault and 200 volts may appear on a Circuit protective conductor :confused5:

 

[Farmelectrics]

split the circut and do your dead test

 

[Sparkyphill]

As said break the circuit back down and check IR's, can only be pressure fault behind a switch, damage to a cable or one of your connections has gone a bit off piste ?

 

[MDJ]

split the circut and do your dead test

Whats a dead test? will my roll of tape help me with this?

 

[Deleted member 26818]

Sounds to me that there's an earth to neutral reversal somewhere.

 

[telectrix]

Whats a dead test? will my roll of tape help me with this?

a dead test is carried out by paramedics after you have energised a faulty circuit that you have not properly tested. they try to find a pulse. if there is no pulse, then you are dead.