New consumer unit - diagnostics challenge

[ban-all-sheds]

TTC's apprentice will put your helmet on her head.

 

[SimonH2]

Indeed, it's partially a consequence of the teaching/practice that there should be no visible copper. I have to say that (despite the flak it may cause), I have always try to adopt the opposite practice - i.e. to be sure that there is always a tiny bit of bare copper visible, to reassure me that I have indeed tightened onto copper, rather than insulation.

Indeed. And in this case it's hard to figure why it's insulated at all. It's not as if there isn't a whole neutral bar in bare copper right there with it.

Mind you, like (I imagine) most of us, I have been 'caught' by this problem. I think G/Y sleeving is perhaps the biggest bugbear. Unless it's very tight on the conductor (and there are not enough sizes of sleeving around for it to always to be tight) it's only too easy to push the sleeving into a terminal whilst holding the wire in place to tighten the screw ... and that's a good illustration of why post-work testing is important, since a non-connected CPC will not otherwise be noticed.

I've observed that. Also had a slight problem with brown sleeving which was the reverse. I blagged a couple of foot off the wholesaler and they assured my it was the right size for 1mm T&E - was it 'eck. It's a good fit and it's only possible to get about 1/2 inch slid on before it's just too tight to go any further. They didn't have the next size up, even after their next delivery.

Thanks for the interesting diagnostic challenge - and glad you got it sorted!

Well I'm glad it was interesting and/or useful to someone.

Here's the inside of the same model of unit, but a different installation. I don't have any pictures of the one in this thread, but the bulk of the space above the breakers is taken up with excess cable - I'd have trimmed them a bit myself, and on this one I've tucked the spare behind each breaker. And I found myself blowing the photo up very big to see if there's any bare copper showing on both ends of the link

Pro-Elec Consumer Unit

• SimonH2
• 17 Nov 2011
• 3

Inside a ProElec Consumer Unit sold by CPC

 

[JohnW2]

Indeed. And in this case it's hard to figure why it's insulated at all. It's not as if there isn't a whole neutral bar in bare copper right there with it.

As you say, it makes little sense. I guess someone was obsessed with the need to 'insulate all conductors', even when they are sitting right next to a mass of shiny metal to which they are connected!

I've observed that. Also had a slight problem with brown sleeving which was the reverse. I blagged a couple of foot off the wholesaler and they assured my it was the right size for 1mm T&E - was it 'eck. It's a good fit and it's only possible to get about 1/2 inch slid on before it's just too tight to go any further. They didn't have the next size up, even after their next delivery.

There's only a very limited range of sizes of sleeving available (basically in 1mm steps), and the insulation of cable cores also seems to vary slightly both in size and 'roughness'. In situations such as you describe, silicon spray can work wonders!

Kind Regards, John.