Replacement CU and no CPC on light cct.

[Jaymack]

What is the current position with installing a replacement consumer unit, where there is no c.p.c. Can the existing cable remain according to the regulations, by placing a label at the C.U. warning against fitting metallic fittings?

 

[westward10]

There is no label/notice in BS7671 to cover this situation.

 

[buzzlightyear]

Yes, but making sure that all switches and pendants are class 2.

 

[westward10]

Yes, but making sure that all switches and pendants are class 2.

Accessories are generally not Class II and such a means of protection is not deemed suitable for a domestic situation which I assume this is.

 

[buzzlightyear]

Best practice guide 1 the op needs to read
Regarding consumer change. Look for electrical safety first.

 

[Wilko]

Hi - in my view the lack of a CPC should be fixed, as the circuit is a fail on the EIC ... which it can’t be, if that makes any sense.

 

[westward10]

Best practice guide 1 the op needs to read
Regarding consumer change. Look for electrical safety first.

The OP needs to use their experience to ensure compliance with BS7671.

 

[pc1966]

My understanding is something like a CU change should result in an installation that is no worse than before in terms of compliance.

No earth for the lights was OK in the distant past (OK probably with all Bakelite fittings) but not now and it might be that rewiring to correct would cost too much for the customer so they would do nothing (no idea, just for argument here). However, having RCD protection on the lights from a new CU is a major improvement in overall safety even with no earth for the lights.

I would be far more worried by perishing rubber and/or signs of insulation failing with old cables, but not my call!

 

[buzzlightyear]

Before any cu change a Eicr needs to be done before hand.

 

[pc1966]

Best practice guide 1 the op needs to read
Regarding consumer change. Look for electrical safety first.

I guess this is the guide you mentioned?

https://www.----------------------------/media/2146/bpg1.pdf

Looks quite sensible, has section 10 on exactly this issue, worth looking over if for no other reason than protecting one's posterior. Seems the TL;DR version is:

• See if they will get it rewired (or dedicated CPC to each accessory, probably as much trouble/cost and less elegant than a rewire), or
• See if all light fittings can be made class II, or
• Insulation test from L+N to each accessory's earth to make sure it is safe at that point in time (I guess including fixing screws on plastic switches?)

The guide has 1M as the lower limit for insulation tests, not sure I would be happy that low, but hey at least it ticks the box of "followed best practice" if asked!

 

[Midwest]

This thread debated this subject and also the ESF Best Practise Guide. #88 I received a reply from ESF, about the conflicting advice between its flow chart & indent 10.7.

No CPC in lighting circuits / Fire damage - in - UK Electrical Forum

, No CPC in lighting circuits / Fire damage, UK Electrical Forum, ElectriciansForums.net Est.2006 | Free Electrical Advice Forum and page_number.

www.electriciansforums.net

 

[pc1966]

This thread debated this subject and also the ESF Best Practise Guide. #88 I received a reply from ESF, about the conflicting advice between its flow chart & indent 10.7.

Thanks for pointing out the thread. Seems the discussion got a bit heated at times! However, I think the main bit to take from all of that thread is one line from the reply you got:

In an ideal world we would not permit such an arrangement but instead the signatories agreed a more risk based approach.

That kind of sums up life really. Ideally no one would want 50+ year old cables without CPC for their lights but if rewiring is not an option for whatever reasons (needed quickly after damage to CU, owner can't afford it, disruption/risk to property too high, etc) then the risk-based approach is to see if it is acceptably safe and the owner agrees to the limitations then it is OK (i.e. cable not a fire risk due to perishing, no signs of insulation failing to the existing accessories).

 

[Midwest]

I am saying nothing.