Bg consumer unit swap issue

[Doc Hudson]

I understand. But when you got a 10 way on the van spare. Thought I'd fit it.  Ramp test was with all circs disconnected and then rcd tested at outlets. Plus I always test ir with cpc disconnected.  Full dead tests nowt connected to board. Ensuring safe to do so of course  I.e customers clients out the way.  Plus 5 way rcbo board extra cost to customer. Due to rcbo prices

From your opening post;  "swapping over a domestic consumer unit due to shower swap and bathroom lights being altered and no rcd present. And previous spark fitting a dreadful cheap plastic c/u. & taking the customers money and run."  After an initial bodge up for the customer, I would have made clear that the wrong product had been fitted, offer them the correct product, (such as https://www.screwfix.com/p/british-general-12-module-6-way-populated-main-switch-consumer-unit/5226j,) If they don't want to pay for a proper solution, walk away. In the process of trying to fit a cheaper board you have in my opinion failed to meet regulation 314.1 (i) and not saved any money because you now have more time and labour trying to hunt and fix a problem. You may have multiple faults? either way a full RCBO board would have saved hours of messing around that you are now doing. (possibly at your own expense losing money on the job). 

If there is some cable damaged giving continuity to earth via the building structure, not directly via the CPC's then doing an IR test between open circuit conductors will not prove anything. You need to know if there is a fault path from L or N back via the CPC or the building structure. (damp walls, damaged cable insulation buried in walls etc.). Your tests so far have not fully tested the circuits nor do they fully comply with BS7671. 612.3.1 and figure 10.3.3. of the on site guide both state that the CPC's must be connected to the earthing arrangements whilst doing IR tests.

In this day and age of easy on-line ordering, and multiple electrical wholesaler outlets, the concept of electricians driving around with a spare fuse box sitting in a van is not the best economic business model. Dead stock is dead money, certain smaller quick fix repair items are normal stock to carry. But I doubt many would be changing a CU without a few days notice, or going to site first to assess what's needed.

I think you will need to go back, break the installation back down and do more testing, depending upon you labour costs, it may be more cost effective to go and buy some RCBO's and reconfigure the board. You may well have to write off a few costs make a loss, but use it as a job to learn from. Don't just fit what you have, offer the customer the correct product, (not the cheapest), to make their life and yours as easy as possible. And make sure you test to earth with all CPC's bonding etc in place. 

Doc H. 

 

[ProDave]

Yes that socket circuit needs MORE testing.

Tripping when you plug ANYTHING in is not "nuisance" tripping, it's showing you there is a fault.

If you really can't find the fault with more testing then I would start by disconnecting ALL the other circuits so you just have the sockets. Does that trip all on it's own?  If it does you have to persist and find the fault. If not start re connecting the other circuits one at a time until it starts tripping again.

 

[Duane B]

From your opening post;  "swapping over a domestic consumer unit due to shower swap and bathroom lights being altered and no rcd present. And previous spark fitting a dreadful cheap plastic c/u. & taking the customers money and run."  After an initial bodge up for the customer, I would have made clear that the wrong product had been fitted, offer them the correct product, (such as https://www.screwfix.com/p/british-general-12-module-6-way-populated-main-switch-consumer-unit/5226j,) If they don't want to pay for a proper solution, walk away. In the process of trying to fit a cheaper board you have in my opinion failed to meet regulation 314.1 (i) and not saved any money because you now have more time and labour trying to hunt and fix a problem. You may have multiple faults? either way a full RCBO board would have saved hours of messing around that you are now doing. (possibly at your own expense losing money on the job). 

If there is some cable damaged giving continuity to earth via the building structure, not directly via the CPC's then doing an IR test between open circuit conductors will not prove anything. You need to know if there is a fault path from L or N back via the CPC or the building structure. (damp walls, damaged cable insulation buried in walls etc.). Your tests so far have not fully tested the circuits nor do they fully comply with BS7671. 612.3.1 and figure 10.3.3. of the on site guide both state that the CPC's must be connected to the earthing arrangements whilst doing IR tests.

In this day and age of easy on-line ordering, and multiple electrical wholesaler outlets, the concept of electricians driving around with a spare fuse box sitting in a van is not the best economic business model. Dead stock is dead money, certain smaller quick fix repair items are normal stock to carry. But I doubt many would be changing a CU without a few days notice, or going to site first to assess what's needed.

I think you will need to go back, break the installation back down and do more testing, depending upon you labour costs, it may be more cost effective to go and buy some RCBO's and reconfigure the board. You may well have to write off a few costs make a loss, but use it as a job to learn from. Don't just fit what you have, offer the customer the correct product, (not the cheapest), to make their life and yours as easy as possible. And make sure you test to earth with all CPC's bonding etc in place. 

Doc H. 

Cheers Doc H 

Going back anyway never been in the habit of leaving a job even if it costs me. Just tried to put a job right as cheap and as good as possible for some pensioners. Yes looks like on this occasion it bitten me in the ass.  Suppose we have all been there at some stage or other. Great advice and knowledge many thanks indeed. By the way I normally do test cpc''s intact. But lost the plot yesterday. I was frantic. Pulling my hair out. 1st time with a major split load rcd headache. 

Thank you. I'm calm today lol

 

[Duane B]

Thats the wrong way of doing it  - all CPC's and earthing must be connected to the CU when conducting IR tests....

Hi murdoch

Headache day. Lost the plot yesterday. With all what was going on and in frantic panic to get juice back on. I was trying g all sorts. And hand on heart I normally test with cpc's connected. But I'm back on planet earth now. Lol. It always happens when you try and do somebody a favor or good turn. Assuming Bite.  Lol. 

P.'s your all a great bunch on here by the way. I'll have to pop in more often. 

 

[binky]

have lost the plot many a time! Lets us know what you find, feedback is always appreciated.

 

[Doc Hudson]

Hi murdoch

Headache day. Lost the plot yesterday. With all what was going on and in frantic panic to get juice back on. I was trying g all sorts. And hand on heart I normally test with cpc's connected. But I'm back on planet earth now. Lol. It always happens when you try and do somebody a favor or good turn. Assuming Bite.  Lol. 

P.'s your all a great bunch on here by the way. I'll have to pop in more often. 

Don't worry Ampsyaman, we ALL have off days and sometimes get bogged down where we cant see the wood for the trees. If any member on here said they had never dropped a clanger or approached a problem from the wrong end they are a liar!  Especially if you are working solo with no one to bat ideas around with. This is one of the functions of the forum that we do try to encourage. Unfortunately occasionally people can take the wrong impression from the intended meaning of a post to what they perceive the meaning is.

Anyway in my personal opinion it takes some balls and a portion of humble pie to admit you were getting flustered so respect to you. And on behalf of the forum would say you are always welcome back here whenever you feel the need. please do come back and tell us how you get on and finally resolve this issue.  

Doc H.

 

[Sharpend]

Totally agree with the Docs prognosis :Applaud  

so do come back  for your next check up  

 

[M107]

Agreed....I know I've been there 

it's even worse during the winter months........just about completed on the job & something goes wrong (yes I've had the old RCD wont reset issue),daylight is rapidly diminishing out side, getting darker inside, the customer wants to get tea on, the kids have come home from school & want the internet on & you now have to start tracing a fault..............yes panic does set in a little.

As pointed out I also fit all rcbo boards for small cu swaps (5 circuits or less) as standard, but always give the customer the option of an all rcbo board for larger swaps as well just point out the additional benefits they tend to go for it.