CU Change - Ring Tripping RCD Low IR

[Cbigfoot]

No i didnt do any testing before i started as it was an old wylex fuse box all the wires were short and twisted together so i thought id do it when i had finished.


My question is, where do i stand with the paperwork if the customer doesnt want to pay to get it fixed.

I did explain before i started that installing a new CU can flag up problems.

You can do an IR between lives and to earth from the busbar, no need to undo any connections.

if you explained that it can flag up problems and wrote it in your quote, i do not see the issue. You told them, there is a problem, it needs sorting.

If he won't pay it iooks like its your loss on this one. The fault needs clearing to connect to the RCD, and certify or you have just installed a white elephant in place of their wylex unit!

 

[Richard Burns]

Check the obvious that your neutrals are in the right N bar!
How low are your IR readings if they are less than 0.007 MΩ then this is a good place to start from
Try and assess the cable runs to look for obvious nails, screws and so forth in the wall at odd points.
But the chances are it is just a socket outlet cable trapped or scraped.

 

[MDJ]

Hi i went to change a CU last night and the ring main is causing the RCD to trip even with everything unplugged.

I am going back today to investigate abit more, i have just left the ring on the non RCD side for the time being.

The customer is as tight as and doesnt really want to pay for me finding a fault "as it worked before"

I am willing to spend abit of time looking for it for my own peace of mind but the house only has 1 ring so i can tell its going to be a nightmare.

Can i issue an installation certificate for the CU with low insulation resistance readings and note it in the comments?

or can i issue a EICR and recommend a rewire?

There is also no earth on the lighting but all the fittings are plastic, so i have recommended that the lights need a rewire.

TBH I am suprised you haven't been beat up over this, (message to the mods) - told you it was calmer now than a few weeks back didn't I :biggrin5:

 

[applemac]

You bad boy, test first, test good fit board. Test bad don't fit board- find fault- fix- test good, fit board. Simples.

 

[telectrix]

recipe for disaster... starting a job when you should already be in the pub.

 

[amberleaf]

Applemac : test first .. sound advice my freind .

dont take for granted , That the ciruit is DEAD .
rewiring . two shops + 3 flats .

it was my fault for not checking the power was DEAD . 99.9% it is DEAD in my case it was 1%

my point is sound . after killing power from two flats , live cables hidden in the plaster , two of the flats have been screwing power for the shop down stair . lighting & sockets . for years . had to get a new pair of Side Cutting Pliers

After all that , the shop was feeding the some of the pub next door . aswell .

is Testing realy needed , YEAH.

Computor shop , in return the shop owner , issuded me with a new computor .
after 3 years , paying othr peoples bills , £700 electric bill he saved on . the landlord ripped up the bill .

teletix . has a vilid point .
look on the bright side. you will have learnt as lesson the hard way. you'll not make the same mistake again. Yes I have . Test , Test , Test .

sorry if mstakes , trying to work this comptor , windows 8 . word 2010

 

[GLENNSPARK]

Possible a trapped neutral in one of the sockets , un plug every thing insulation test , it the old thing when you do a consumer upgrade "well it worked before " just explain how the RCD works with the old system working with a neutral to earth fault where as the new wont good luck in finding it

possiby a fault that a 3036 wont `see` as well....

(assuming the previous board was utilising these fuses that is)...

 

[MDJ]

possiby a fault that a 3036 wont `see` as well....

(assuming the previous board was utilising these fuses that is)...

Afternoon Glenn

 

[NickD]

i have just left the ring on the non RCD side for the time being...The customer is as tight as and doesnt really want to pay for me finding a fault "as it worked before"...There is also no earth on the lighting but all the fittings are plastic, so i have recommended that the lights need a rewire.

Interesting as others have said that your board has a "non-RCD side".

Presumably the job is building control notifiable, is client notifying or are you on their behalf? What's going to happen about that if the sockets are not RCD protected (departs from BS7671), would you sign off on the EIC and notify with it like that?

What did you contract with the client to carry out (i.e. should fixing that ring be an extra charge)?

Don't forget the unearthed lighting warning sticker.

 

[NickD]

(message to the mods)

...



...

 

[Geordie Spark]

 

[dazza1981]

" When the going gets tuff " the op gets going pmsl

 

[tony mc]

Lets us have your dead test results on the ring and we might be able to shed some light also is it in twin & earth 2.5/ 1.5 or 2.5 /1.0 .

The IR readings are they in K ohms or Ohms money on a Neutral to Earth bad reading !!

 

[HappyHippyDad]

Heres a couple of links for you Firewalshy regarding CU changes. I find the checklist very useful and have made the same mistake as you.... Once!

It's nice to see the forum being a bit less harsh :smile5:

http://www.electriciansforums.co.uk...ctrical-regulations/12971-cu-changes-you.html

http://www.electriciansforums.co.uk...ectrical-forum/83094-cu-change-checklist.html

 

[tony mc]

I take it that you found the fault and protected the cct with a RCD !

Let us know what the fault was !

Thanks.