Refused to install metal light fitting

[isk57]

Today I had a quick job on the way home which was swap a pendant for. Fancy light fitting , but when I removed the pendant there was a pre 1966 2core twin cable And a separate 2.5 single earth cable fairly new , it looks like someone has gone around every light with the earth from the board to give it a cpc.
there was a good Zs but I still refused to install the light with the cables not being up to standard .
Thoughts please

 

[Pete999]

Today I had a quick job on the way home which was swap a pendant for. Fancy light fitting , but when I removed the pendant there was a pre 1966 2core twin cable And a separate 2.5 single earth cable fairly new , it looks like someone has gone around every light with the earth from the board to give it a cpc.
there was a good Zs but I still refused to install the light with the cables not being up to standard .
Thoughts please

What's wrong with that then?

 

[Baddegg]

No different to doing it in singles, 2.5 mm cpc on domestic lighting circuit bit of overkill but.....readings good and continuity confirmed.
I’d issue a cert detailing it though I think, even if it is just changing a light fitting.

 

[Andy78]

I'd have installed it if the continuity and reliability of the earth path was confirmed.
Would have advised the same assessment with any future metal accessories too.

 

[SparkyChick]

No different to doing it in singles, 2.5 mm cpc on domestic lighting circuit bit of overkill but.....readings good and continuity confirmed.
I’d issue a cert detailing it though I think, even if it is just changing a light fitting.

As I understand it, when running a separate CPC, it should be oversized to provide additional mechanical strength. I've done this by running a 4mm from a socket circuit.

But I agree, refusing is possibly overkill.

Edit:- I should add, the socket circuit was used (ring final) as being a ring, the integrity of the source CPC is likely to be maintained for longer, the cable was routed as closely to the existing lighting cabling as possible and it was a last resort as getting back to the consumer unit was not possible without major upheaval. It wasn't my first choice, which was a partial rewire (client didn't want).

 

[Baddegg]

Have a read of that op,

 

[ferg]

I think I'd have connected it TBH.
From memory a CPC should be 4mm if not mechanically protected.

Perhaps a note on a MWC or on the invoice highlighting this.

 

[A032701]

if you said the results were good for continuity then i would have fitted it. different matter if there was no cpc

 

[davesparks]

No different to doing it in singles, 2.5 mm cpc on domestic lighting circuit bit of overkill

Unless it's got mechanical protection it is undersized as the minimum size would be 4mm according to the regulations.

 

[Toneyz]

I tend to agree with the above if the continuity is good, the CPC follows the existing circuit route and the loop reading is find I would have connected it. The only note that I would make is that it should be a 4mm CPC as not mechanically protected. In practice, I don't think that's going to be a problem if clipped to the joists.

 

[telectrix]

if cable is secured in the void between ceiling and floor, does thatnot count as mechanical protection? it's only like being in oversized trunking.

 

[LeeH]

if cable is secured in the void between ceiling and floor, does thatnot count as mechanical protection? it's only like being in oversized trunking.

Is a house one large enclosure then?

I would say you’re stretching the rules a little..

 

[Wilko]

Unless it's got mechanical protection it is undersized as the minimum size would be 4mm according to the regulations.

I agree, the Electrician who “fixed” the original problem didn’t use the right size conductor, which is a shame.
However, my thought is our man @isk57 was there doing a like for like replacement and found a satisfactory earth in place, so I’d likely have thought “not good, but not dangerous” and connected the replacement fitting.

 

[Squid]

Is a house one large enclosure then?

I would say you’re stretching the rules a little..

Most houses are enclosed........

 

[Midwest]

I had a job to connect a metal luminaire with singles cpc. Zs was good, didn’t check continuity, but as it was on first floor , went into loft space to investigate. Traced single which was clamped onto copper pipe in loft. Didn’t fit light.