Nightmare of a day. RCD tripiing under any load

[brizospark]

Have had one of them days. I had a board change to do and a few other bits and bobs so everything was going great until I tried to put power back on.

Basically I have replaced a 3036 board with a split load Wylex board. One half of the board is working fine but the other half's RCD is tripping as soon as anything is plugged into it.

If I remove all plugs from sockets then the RCD holds but as soon as I plug anything in, kettle, sky box, TV, it trips instantly. On this side of the board is the cooker, 1 x lighting circuit and 2 x ring mains, funny enough the RCD isn't tripping when the lighting circuit or cooker is on.

Now I have checked that I have neutrals from correct circuits going to the correct neutral bar, several times and these are OK. I tried replacing the RCD itself with the one that was OK and it still tripped. What else is strange is that the kitchen ring is on the side of the board which is fine but if I plug anything into a kitchen socket the RCD which isnt even protecting this is tripping!! I opened up sockets and everything looked OK but it was getting late on so I replaced the offending RCD with a main switch I had in van just so the couple have power on tonight before I go back again tomorrow. Switched on with RCD removed and everything fine.

Anyone had experience with this problem before? Any advice much appreciated

 

[marcusone]

Eng54 do you honestly think in the real world customers would give the go ahead to carry out testing before changing a board? This would mean an additional cost on top of a board change The customer would simply get someone else to do the job!

Its not an additional cost. Its part of the cost of doing the job right from the start. Not every customer wants it cheap, most want it done once and done right.

 

[Guest111]

The problem you know have is a potentially peed off client,did you leave them without power last night? And possibly a lot more work to do if it's not a quick fix,if you test thoroughly before swapping the board any issues will be found and corrective action and any further costs can be discussed with client.

 

[Engineer54]

Eng54 do you honestly think in the real world customers would give the go ahead to carry out testing before changing a board? This would mean an additional cost on top of a board change The customer would simply get someone else to do the job!

What do you mean extra cost?? The Minimal IR/ELI/Shared Neutral tests are for ''YOUR'' benefit, so that you know, or are aware of any problems, (such as you have now) before you start!! Armed with that information, you can advise your customer of any extra costs that will be associated with the board change!!

 

[GLENNSPARK]

Sounds like borrowed neutral to me. Have u tried putting the 2 lighting circuits on the same rcd?

eh...?
its on the socket....

 

[GLENNSPARK]

Eng54 do you honestly think in the real world customers would give the go ahead to carry out testing before changing a board? This would mean an additional cost on top of a board change The customer would simply get someone else to do the job!

what a bunch of old twaddle this is...

having read all this its clear to me you are not competant to carry out board changes....

leave such stuff alone until you have gained the necessary experience

 

[Sharpend]

Brizo, no disrespect but you may need to shadow a more experienced spark, if not to improve your knowledge, them to learn the correct proceedure and why it's correct.
Are you fresh out of training?

 

[SJD]

Eng54 do you honestly think in the real world customers would give the go ahead to carry out testing before changing a board? This would mean an additional cost on top of a board change The customer would simply get someone else to do the job!

When you have completed the CU install, you will have a completed test sheet with the test data for each circuit (I hope), so you can just as well do some of that testing before doing anything to the old board, just in case it throws up things like N-E faults, or broken rings etc. There is minimal extra cost, but potentially saving a lot of embarrassment.

 

[Guitarist]

Eng54 do you honestly think in the real world customers would give the go ahead to carry out testing before changing a board? This would mean an additional cost on top of a board change The customer would simply get someone else to do the job!

I have to agree with Eng here. Basic tests at the time of quoting take 20 mins tops, and save a world of pain down the line. Also, the added bonus of carrying out a few basic tests gives you time to chat to the client and show them your shiney MFT. They get to know you, see that you are competent, and will usually give you the go-ahead there and then. Much better than someone who pops in for 2 minutes, gives a rough quote, then adds to the bill later on when the issues raise their ugly head.

 

[Brightspark2]

I know it's like an echo now but I agree with the above comments, testing should be done before you change the DB. I wouldn't change one without testing otherwise it just comes back to bite you like this. Then the customer rolls the old "well it was fine before".

 

[Chris sparky]

I know it's like an echo now but I agree with the above comments, testing should be done before you change the DB. I wouldn't change one without testing otherwise it just comes back to bite you like this. Then the customer rolls the old "well it was fine before".

Same as this. If they have had a quote off another "sparks" who's cheaper because he is going to lash it on and hope for the best, then let em do it. You may well get the call when it goes ---- up :smug:

 

[GLENNSPARK]

I have to agree with Eng here. Basic tests at the time of quoting take 20 mins tops, and save a world of pain down the line. Also, the added bonus of carrying out a few basic tests gives you time to chat to the client and show them your shiney MFT. They get to know you, see that you are competent, and will usually give you the go-ahead there and then. Much better than someone who pops in for 2 minutes, gives a rough quote, then adds to the bill later on when the issues raise their ugly head.

pervert...

 

[Knobhead]

Eng54 do you honestly think in the real world customers would give the go ahead to carry out testing before changing a board? This would mean an additional cost on top of a board change The customer would simply get someone else to do the job!

So once again we have a Electrical Trainee showing the vast depth of their knowledge (stupidity).

You won’t do any pre-testing because it’s going to take time. Time that you have to spend later when things don’t work as they should! If I was the customer, my reaction would be quite rightly “it worked before you messed about with things” I wouldn’t pay you for any extra work because I would think you were pulling a fast one.

 

[Deleted member 9648]

We dont pre-test where a client has asked for a quote for a cu change,a visual is enough to see if there are likely to be problems and it is made clear in the quote that full tests will be carried out and problems may incur extra cost. I'd agree that an IR test prior to quoting would be a good idea,but even if the IR is ok what about continuity?...ring continuity?...problems here will still need sorting and wont be apparent unless full testing is carried out.I'm not going to spend time doing a full set of tests for a quote I might not even get.
I can honestly state that problems encountered on my CU changes only ever take an hour or two to sort.Only on one occasion did we come unstuck,an apparently unmolested installation turned out to be big time DIY'd,IR faults-breaks in ring continuity-all earths cut off at JB's under floor.Took 2 days to sort,luckily client was able to witness the carnage and was amenable to sorting it.....clearly though this is one where we were wide open to the 'test before quoting' school of thought! It is clear that the OP does not understand testing and fault finding and is out of his depth,this sounds like a simple fault....whats the betting these RCD's get bypassed and he walks?

 

[Kate]

I know it's like an echo now but I agree with the above comments, testing should be done before you change the DB. I wouldn't change one without testing otherwise it just comes back to bite you like this. Then the customer rolls the old "well it was fine before".

When asked to do fuseboard change I make it crystal clear to the customer that I have to check existing electrics beforehand. Any faults found would incur extra costs.

 

[GLENNSPARK]

We dont pre-test where a client has asked for a quote for a cu change,a visual is enough to see if there are likely to be problems and it is made clear in the quote that full tests will be carried out and problems may incur extra cost. I'd agree that an IR test prior to quoting would be a good idea,but even if the IR is ok what about continuity?...ring continuity?...problems here will still need sorting and wont be apparent unless full testing is carried out.I'm not going to spend time doing a full set of tests for a quote I might not even get.
I can honestly state that problems encountered on my CU changes only ever take an hour or two to sort.Only on one occasion did we come unstuck,an apparently unmolested installation turned out to be big time DIY'd,IR faults-breaks in ring continuity-all earths cut off at JB's under floor.Took 2 days to sort,luckily client was able to witness the carnage and was amenable to sorting it.....clearly though this is one where we were wide open to the 'test before quoting' school of thought! It is clear that the OP does not understand testing and fault finding and is out of his depth,this sounds like a simple fault....whats the betting these RCD's get bypassed and he walks?

often the case..
i was on a board change over in Bradford yesterday....there were 2 existing circuits that had no chance whatsoever of going into that new board....
i didn`t bother testing them....failed visual they did...