CU change

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PIP IOM

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Howdy guys

doing a C/U change at a job where 3 lightin ccts have bad readings 1./ dead short (original fuse blown) obviously not re-connecting that one, 2/3./ have .21 and .4 IR readings. The house is unoccupied and pretty mouse infested at the moment.

Obviously strongly recommending full PIR/poss part whole rewire.

I've re-connected (temp only) ccts 2/3 and the RCD's don't trip

There is also a 6mm G/Y to rthe airing cupboard bonding some pipework.

I've put in 10mm to services etc should I leave out the 6mm or put it back in

Owner arrives back mid Dec and he wants to stay in his house for a few weeks before heading back to Brazil. Going by the "changing CU doc" i just have to inform him of any non-compliant circuits that I've re- connected.

Rambled on again, but potentially loads of good work here

any advice?

 
Surely it's better to agree with him to sort out the problem circuits.

Yes mouse damage, and even a dead mouse is likely.

I was called to a tripping RCD last week, narrowed it down to one ring main. Start separating the legs of the ring, until I locate the fault as being on the legs that connect to the CU. Open CU and there is a dead mouse slumped over that MCB. Should have checked there first.

In your case look for mouse damaged cable in the loft or under floorboards. Look also for damp in back boxes, back boxes full of dust and debris etc etc.

With readings that low I wouldn't be happy leaving them even if the RCD didn't trip

You say RCD doesn't trip now, but surely the lights are not on an RCD yet? If they are then the CU is so new why are you changing it?

 
sorry Dave facts once again lost in the drivell.

I've changed the CU

I've done the CU tests (R1 +R2/IR/Zs etc)

He's coming home soon and i want to know if i can leave the low readings ccts energised (as they were with old fuseboard) just to give him adequete lighting

Then negotiate future work

 
If you've changed the cu then you've got to issue an eic. On an eic there cat be any non compliances can there? So I would have thought that these circuits cannot e reconnected?.

I think that's why people do a pir first so that you won't get stuck in the situation your in mate.

Sorry

 
My understanding is you offer a PIR (declined in this instance)

Then you change the CU completing the minimum tests stipulated in the electrical safety council best practice guide C/W 7671 of course

I'm just in a quandary about this "do i leave him with no lights/do i reconnect and detail on my EIC (as stated in ESC doc) or do i do something else scenario"GuinnessGuinnessGuinness

 
IF customer is offered PIR and declines;

AND you go ahead with CU change anyway.

THEN you must either leave all non-compliant circuits disconnected;

OR resolve the relevant issues.

As I said on another post, look at the "best practice guide" for replacing domestic CUs - lots of useful info.

 
PIP let me know if you need a SPARK to come have a look for you, I know quite a few actual electricians on the Isle Of Man that will happily come sort out simply issues like this for you.

 
I am a SPARK

I will sort these issues out

Was just getting opinions (thought that was what the forum is about)

Won't bother again

 
in my opinion you should never leave ccts energised that have problems with them. Therefore if this leaves the occupier with no lights so be it, he will have to agree to the work being done before he comes back to the property.

Another reason i allways offer the pir before consumer unit change, that way if theres problems with any ccts the customer will know.

 
Pip.

In the esc bpg it says

5.2. Bs7671 does not require existing circuits to be upgraded to current standards in order for them to be connected to new board.

5.3. However circuits that are defective or non compliant with the requirements of bs7671 in a way that would result in real and immediate danger must not be connected to the consumer unit.

Will your circuit be dangerous if you connect the lights up?

I may be Reading it wrong but is this what you were Reading in the bpg mate?

Cheers

---------- AUTO MERGE Post added at 09:40 ---------- Previous post was at 09:36 ----------

Also it goes on to say

5.7. Any defects found in the reconnected circuits must be recorded on the eic covering the replacement of the cu, as required by reg 633.2.

633.2. The contractor or other person responsible for the new work shall record on the eic or mwc any defects found, sfarp in the existing installation.

What do you guys recon on this?

 
Even if it was okay to reconnect circuits with such low IR readings, surely you just setting yourself up for him to call you back when it trips?

Never reconnect and leave a circuit with low IR!

Spend an hour or so trying to fault find the problem and see if you can get some lights back on, then if you cant tell him its chargeable/needs rewiring?

When quoting for a board change i always like to do a quick IR test/ELI just to check theres no major probs, however this is not always possible. Its rare that i get to do a PIR first.

Those who do, do you charge for the PIR, then the board change? Or combine both into one cost if they decide to go ahead, and charge for PIR only if not?

 
the way I do it is:

1) Explain the situation to the customer about the possibilty of problems when the new CU is fitted and explain that if it is not tested first to identify the problems then any remedial work afterward the change is CHARGEABLE.

2) PIR the existing installation. If it fails, explain to the customer the problems (In basic terms!) If they don't agree to the remedial work, charge them there and then for the PIR and issue them with their failure cert.

3) If they agree to the remedial work, investigate the problem(s) first for an amount of time......usually it will be something simple like old metal fittings etc which can be changed for basic pendants etc.

4) Change the CU, do all the relevant TESTS that weren't carried out in the original PIR ie: RCD, "Zdb", PFC, trip times etc.......remember that you've already done the best part of the test anyway on the conductors before the change.

5) Take payment and issue cert.

Remember that a CU change is notifiable so will need an EIC so this must be figured into the price of the change, it does not matter which way around the conductors of the installation are tested ie: before or after but it saves a load of grief if you do it FIRST!

All IMO and the way I do it.

 
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