Earth/ CPC very high potential

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

JACCD

Member
Joined
Mar 23, 2017
Messages
19
Reaction score
-1
Location
Surrey
Hi all, looking for some advice for a rookie please.  This concerns a 2-way lighting circuit, that's to have some LED downlights to replace old halogens.  It was just to be a replacement of lights so a ran a quick Zs test beforehand and MFT sounded "voltage/ polarity" alarm.  From the supply side I'm getting L-N 240v but L-E and N-E at 12.3v.  So Earth/ cpc has a very high potential.  No voltage on it itself with the voltage tester.

There's some very poor wiring in the property so I'm looking for some advice please on where to look and test to find the issue.

Many thanks

 
Thanks I will do that's very helpful.  So nice to post a question asking for advice and to actually get some.  On other forums you just get abused!

 
Thanks for your comment.  They teach what they teach and you have to keep learning afterwards.  Not going to apologise for that.  Everyone was new once.  Just came on and asked for some advice.

 
Thanks for your comment.  They teach what they teach and you have to keep learning afterwards.  Not going to apologise for that.  Everyone was new once.  Just came on and asked for some advice.


youre part right... you do still keep learning afterwards, but this is basic stuff that you should be well aware of

so what did you tell your customer? 'my test kit said there was a fault, but since i dont know how to use it or understand what it says ill come back tomorrow after i go ask on a forum for their advice'?

 
C'mon guys.......  :shakehead

Surely it's better to learn from someone than just make it up as you go along? 

The current system,  as much as its disliked is here to stay until they run out of gravy. 

:|

 
Last edited by a moderator:
I'd hazard a crazy guess that you are replacing ELV MR16s with GU10 LEDs , and some very astute person has simply cut the CPC off at each previous fitting.

:shakehead

 
I'd hazard a crazy guess that you are replacing ELV MR16s with GU10 LEDs , and some very astute person has simply cut the CPC off at each previous fitting.

:shakehead
I am doing EXACTLY same at sons new house today

place is a total nightmare...only got keys last week !

BUT the only thing that is right is that all the M16s have the Earth in the T&E connected through!

REEEEEESULT as it is a flat roof

extension and conservatory and new kitchen and two new bathrooms within last ten years

NOT an RCD in sight

gas bonded on lead on incoming side

not an IP fitting in any bathroom

no paperwork for loft ensuite conversion

no steel,calculated 

no building regs

nohing for anything really........I,see it being a busy summer

 
You mean our best friend the ..............plasterer who thinks can do " a bit of electric"  too. 

Just agreeing with The Duck ...this Forum is a bit different ...can't we help the guy out .  

I don't remember college telling me about an unconnected earth wire collecting induced voltages ......I think there was a huge list of stuff I only learned "on the tools"  from other sparks .  

Top of the head ....college didn't tell me that those circular fluorescent tubes are unlikely to strike with an FSU  starter  ....starter needs to match the tube watts .

Same with some ..(but not all) ....6 ft fluorescent ...some makes you can try  FSUs all day long  although they're marked up 38-- 58--70 w they won't strike ......only work with a 70w starter.

College didn't tell me how to connect a 3Ph  motor starter as 1Ph . etc 

 
I know that Murdo ... :Salute     just that I found that many younger sparks just on the tools ....AND... a lot of guys working for bigger firms on larger installation jobs hardly ever found themselves fault finding ..and some ..very little practice working live , fault finding etc. 

 
Top