Consumer Unit Chaos

[securespark]

As promised some time ago, here is a photo of my latest CU challenge.

All CU's apart from the brown one to the left of the meter are dead (although all except the r/h unit still have a live feed from the meter). The main CU is fed via a metalclad switch fuse (32A) via fabric covered tails of (equivalent) 6mm2.

The service head has been changed after a huge battle with the REC. Originally, the main earth (4mm2) was attached to the sheath (very loosely!) by an EC14. There was a rather large indentation in the lead sheath where the clamp had been. And the engineer looked at it and told my customer he didn't know what I was worried about....I had to talk to him to try and convince him otherwise. Oh, and the main fuse was 40A....

Anyway, enough bleating. Here's the picture!

That's my wrist at the bottom of the pic... The CU is under the stairs, so I had to shoehorn my fat long carcass into a very small space in order to get everything in the frame. I'm still dieting!!

 

[plugwash]

i think its a case of rip all the CUs out and run fresh tails to a modenr split load CU direct fomr the meter

 

[securespark]

Yes! But what a feast for the eyes!!!!

 

[Lectrician]

I have seen worse, but no pics

Saw a very similar setup, but with several meters. The house had beem split to include some granny annex's. The whole kitchen wall was covered in DB's, S'fuses and meters. A curtain covered the mess

 

[ban-all-sheds]

The service head has been changed after a huge battle with the REC. Originally, the main earth (4mm2) was attached to the sheath (very loosely!) by an EC14. There was a rather large indentation in the lead sheath where the clamp had been. And the engineer looked at it and told my customer he didn't know what I was worried about....I had to talk to him to try and convince him otherwise.

So they gave you a TN-C-S instead by the looks of it? Is it true that a lot of DNOs are doing this because the buried service cable sheaths are deteriorating to the extent that they can no longer be relied on to provide a good route back to the star point?

I see little in the way of main bonding, and the main earth from the CU doesn't look like it's 16mm²......

 

[Lectrician]

In my experiance, a service head with an exposed earth connection is sually manufatured for use on a TN-S system. With PME, the earth terminal is usually enclosed, with just the screw heads visible. (although I have seen PME's with the service head shown).

 

[kai]

That very thin earth wire from the top fusebox to the main earth terminal looks far too thin for a TN-C-S earth, which now requires 16.sq.mm. minimum.
It looks like a piece of 1/.044". to me!

At least you have a highly unusual installation, where the service fuse block is the newest item in the whole meter cupboard area - most such installs have a rusting service fuse block, with a decaying lead service cable, feeding a shiny new consumer unit with MCBs in.

 

[securespark]

AND rcd, kai!!

That thin wire only "feeds" some disused fuseboxes at the top - guess the REC had to reinstate it...

Ban

No, it's still TN-S, there is no link to the neutral inside the head. The main earth to the cu is 4mm2. Of course, that will change.
And don't PME supplies have to labelled as such?

The main bonding is a sore pont. I have quoted for bonding but the guy refuses to have the work done because it involves a lot of disruption to the decor. The water pipe is by the back door, buried in concrete behind an architrave, with just the tap handle visible. I have never had a refusal for work like this, so rang the IEE for advice. They said I should draft a letter explaining that I cannot be held responsible for any problems the lack of bonding may bring and that I shall do the work only on this understanding. He was happy to sign the letter, but I still feel a little uneasy - if his house burns down, what then?

 

[dw3101]

cant you just bond in kitchen / bathroom or as close as you can, and then put a copy of the letter with your records and also put one with his CU and request that he sends one to his insurance company (that might pursuade him)

How you going to add your new tails for your CU?? is there no tag on the meter?

David

 

[plugwash]

i can't see any seals on that service fuse or meter

and even if there are seals many sparkys will just cut them (some i know have even been given bags of seals by rec sparks)

if you want to steal leccy (which i personally don't) then round your meter is probablly the worst place to do it anyway.

 

[securespark]

Yes, the REC left the seals off so I can fit the new ones direct to the meter and pull the main fuse at the same time. Well, strictly spaking, I'll pull the fuse a few seconds BEFORE connecting the new tails...hehe...

Then all I have to do is leave a completion cert for the REC and the customer can ring them to make an appointment to seal up at his convenience.