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

 

[Sparkie30]

You say your not a Electrical Trainee and have done 2391 so my question is what the hell are you doing energizing a replacement consumer unit when clearly you have not undertaken any testing! Sorry but clearly you should go back to college!

With regards to no time to test prior I always always book a 5 minuet slot in at the end of a day prior to starting the replacement CU usually on way home from a job to do 2 IR Tests!
1. IR - LE
2. IR - NE

This takes about 5 minuets to do and will never put you into this situation where you have a not tested CU which you have energized and "TRIP"

so you telling me you learnt everything in college? i think i know the answer to that mate

 

[LED Lighting]

Ok so if you have a customer half an hour away you will travel there at the end of a day grafting to carry out a few tests then go there the next day? You obviously have more time than me. Well sorry mate but that's not for me and I can guarantee you 99% of sparks wouldn't do this either!

With regards to energising the board prior to testing. In a newly wired job I would not do this but because it was a straight replacement I will admit I do this and again so will the vast majority of other sparks

What a load of HOT AIR!

Yes I have had some CU Changes some 3 hours away and every time if its not practical I always IR before undoing anything!
You dont need to unplug anything anything as at the end of the day your only "PAT Testing" the appliances and installation all at the same time!

This is an added bonus because if an appliance has a fault then you can quickly identify this before starting.
I did this the other week - Dead short NE and <1Mohm LN and LE. Advised them it needed fault finding at rate which they agreed to - spent 4 hours and over 50% of cables where shot! went from CU Change to rewire like that!

 

[LED Lighting]

so you telling me you learnt everything in college? i think i know the answer to that mate

Not at all - just clear basics - dont energize circuit unless you tested it!
Common Sense sorry

To brizospark

Forget the IRs for a minuet as that will be picked up with the RCD, but what about no continuity on conductors and you have protected 2.5mm broken ring with a 32A!

Sorry cowboy springs to mind - and considering you need to issue a certificate how do you get these results? Disconnect everything again to retest it? Or make up the results?

 

[Paultrim123321]

If people are suggesting they have been asked to come in and replace the CU...who is making that decision? The client?
If someone rings me and asks to have a CU replaced I would want to know why they think it needs changing?

As the inspector that is up to me.

If a CU needs replacing there's every chance the wiring will need attention, therefore surely testing has to be carried out?

 

[Guitarist]

What a load of HOT AIR!

Yes I have had some CU Changes some 3 hours away and every time if its not practical I always IR before undoing anything!
You dont need to unplug anything anything as at the end of the day your only "PAT Testing" the appliances and installation all at the same time!

This is an added bonus because if an appliance has a fault then you can quickly identify this before starting.
I did this the other week - Dead short NE and <1Mohm LN and LE. Advised them it needed fault finding at rate which they agreed to - spent 4 hours and over 50% of cables where shot! went from CU Change to rewire like that!

No wonder the local sparks are complaining!

 

[moospark]

3 Hours away? Hadaway! I could be in Wales by then.

 

[sima24]

I never test when quoting. I provide a quote for board and explain in simple terms that any faults that are found (if any) will be charged accordingly. Also i agree with some posts that this situation seems very simple, no disrespect to poster but i would have known this fault as a 1st / 2nd year apprentice. Qualifications are one thing but nothing without the experiance.

 

[moospark]

And what does "every time if it's not practical I always I.R" mean?

 

[sima24]

Fault in my view is simply 1) borrowed neutral or 2) n-e fault (which would of been found on dead tests). Simples

 

[growler]

have you checked that the neutrals from the rcds and main switch are in the correct neutral bars ? this caught me out before !

 

[Guitarist]

So you guys who don't bother testing are happy to give the customer a surprise when the bill doubles at the end of the job?

 

[trev]

3 Hours away? Hadaway! I could be in Wales by then.

Gadgies waalkin tho marra, nee van lyk

 

[brizospark]

So LED you say you do this for board change three hours away. So you are telling me after a day working you will drive a six hour round trip to do two IR Tests then go back next morning ? WTF? Are you for real? How much are you charging because the fuel cost alone would be ridiculous

 

[moospark]

Gadgies waalkin tho marra, nee van lyk

Nah, He'll ride his sheep. All the way.

 

[wersolaruk]

Some proper tools on here like! Give the guy some slack! Everybody needs help once in a while.