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Jamie181191

Hi guys I've been doing a partial rewire. And I have taken a feed from a light that is fed, to feed a switch in a new extension. I wired up the lights and switch in the new extension but the light would not turn on. I measured the voltage at the light that's not powering up L-N and I'm only getting 160V, that's the same reading I got with L-N with the new feed. I couldn't test L-E of the feed because it would trip the RCD covering circuits the client needed to stay on. So I tested between the feed permanent Live with SL Earth and got reading of 91 pd. I belled out all the cables and no cores are touching one another which I thought would be the case with no tripping happening at the board. I then went to the light I fed and I was getting again low readings on L-N but the full 240 on the permanent Live bar to the dead SL. The light I fed it from is working and I was thinking maybe I've mixed up a neutral with a live but then I'm thinking I'm going mad cause the MCB would trip. So yeah just a bit stuck on this any info would be appreciated.
Thanks
 
I couldn't test L-E of the feed because it would trip the RCD

Why would it trip? What were you testing with?

So I tested between the feed permanent Live with SL Earth

Not sure what this means...

What are your continuity results? R1=? Rn=?
 
Sounds like a voltage checker ... what are your other testing results as above ... we cannot help if you don't follow testing procedure with results.
 
Not once have I had it trip an rcd wheneasuring voltage... Sounds a bit odd!

that term belling out, sounds like an old school term that's been picked up my a newbie who doesn't fully understand what it means if asked to explain.
 
Not once have I had it trip an rcd wheneasuring voltage... Sounds a bit odd!

that term belling out, sounds like an old school term that's been picked up my a newbie who doesn't fully understand what it means if asked to explain.


I'd guess by his tag he's 24 ish ..not wise to put DOB unless you want to be easily tracked ;).... Jamie if you wish to remain anonymous ask a mod' to change your profile name, you have given too much info if thats your DOB and location.
 
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Not once have I had it trip an rcd wheneasuring voltage... Sounds a bit odd!

that term belling out, sounds like an old school term that's been picked up my a newbie who doesn't fully understand what it means if asked to explain.

It all depends what the voltage is being tested with, a modern AVI is unlikely to trip an RCD unless there is a high earth leakage already. A Drummond type tester or a solenoid tester on the other hand probably will trip it.

Having said that I used to have an AVI that would trip 10mA RCDs.
 
Just noticed your a Trainee Jamie ... Pm a Mod or ask on here for access to the trainee section .... on the main forum you are assumed fully qualified unless you state it in your opening post ... in the trainee section the help is suited to your level.

PS welcome to the forum.
 
I've got the fluke T5-1000 testers and every time i tested live to earth in this house it has tripped the RCD. I thought it was weird but I briefly remember it happening when I was involved in a rewire of a hotel. So Instead of testing between live and earth of the feed that links out back to the board I tested the feed live and the earth of a different cable at the switch that I disconnected to see if I could get the 230v potential difference. I'm starting to think its a loose neutral connection somewhere down the line but I'm not 100%, I will do the full sequence of tests tomorrow to give you a better ideas, it is a vague explanation of my situation. Thanks for reply.
 
It all depends what the voltage is being tested with, a modern AVI is unlikely to trip an RCD unless there is a high earth leakage already. A Drummond type tester or a solenoid tester on the other hand probably will trip it.

Having said that I used to have an AVI that would trip 10mA RCDs.


True, I didn't think about that, I guess you get used to the equipment you use every day!
 
Jamie I have sent you a pm regarding the Trainee section.
 
haha. jamie, just seen that your birthday is same date as mine, except for the year, of course.
 
Hi guys I've been doing a partial rewire. And I have taken a feed from a light that is fed, to feed a switch in a new extension. I wired up the lights and switch in the new extension but the light would not turn on. I measured the voltage at the light that's not powering up L-N and I'm only getting 160V, that's the same reading I got with L-N with the new feed. I couldn't test L-E of the feed because it would trip the RCD covering circuits the client needed to stay on. So I tested between the feed permanent Live with SL Earth and got reading of 91 pd. I belled out all the cables and no cores are touching one another which I thought would be the case with no tripping happening at the board. I then went to the light I fed and I was getting again low readings on L-N but the full 240 on the permanent Live bar to the dead SL. The light I fed it from is working and I was thinking maybe I've mixed up a neutral with a live but then I'm thinking I'm going mad cause the MCB would trip. So yeah just a bit stuck on this any info would be appreciated.
Thanks

Jamie, if I was in your position I would get permission to gain access to the Trainee Forum, you will get lots more help in there with out the sarcastic comments, and perhaps you could explain exactly what you have done withe aid of some simple drawings of the connections. A picture paints a thousand words as they say.
 
Jamie, you haven't tapped into a switch cable rather than a loop feed cable have you? Daz
 

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