How to connect 2 sockets to one 27A cable without ring

[JamesF]

Yes, we're in the middle of nowhere.

We certainly have RCDs on all the feeds to consumer units (of which there are a number) and there is an earth rod outside. There is an earth cable in the incoming head adjacent to the neutral though. I'm not sure that means the two are actually connected however. It might just be that the earth comes into the house with the supply and that's a handy way to get it out.

It gives me fits just looking at it, and I'm not a trained electrician. I do want to get it all re-wired at some point, but there's other stuff that has to happen before that (so the new gear has somewhere to go, basically).

James

[themadhippy]

Never seen a reg that says no...

its in there somewere,or possible in the electrical supply’s act,there was a pretty picture in the back of the on site guide.

I know the transformer in our field

so possible requiring protective devices capable of handling a higher short circuit current than normally required domesticly/outside of london

[JamesF]

For giggles, here you are. This is the primary distribution point for our electricity supply. Missing off the left hand side is the meter and isolation gear for the solar PV.



James

[themadhippy]

To be honest it dont look to bad,yea its a bit messy,but nothings jumping out to me saying "lethal"

[JamesF]

I'm sure they'd have told us if something were seriously wrong when the PV was installed, but there's stuff I've found out since that makes me nervous. Like only a couple of months ago I found that a supply to a CU In a barn actually comes off a 20A fuse on the main CU and is delivered there on about thirty metres of 4mm T&E inside some MDPE water pipe. Fortunately it was very little used and I'm in the process of getting it replaced. I was a bit cross about that one, especially as I originally planned to nick it for the brew shed.

James

[themadhippy]

Like only a couple of months ago I found that a supply to a CU In a barn actually comes off a 20A fuse on the main CU and is delivered there on about thirty metres of 4mm T&E inside some MDPE water pipe

.
the only problem there is the pipe aint orange,the cable is mechanically protected,4mm can easily take 20A,and at 30 meters the volt drop and loop impedance will easily be within the limits of the regs

[Pinto]

Curious - from the looks of the head, you have TN-CS, but RCDs and the earth rod are from TT. Guess you've been "upgraded" at some point but the earth rod was left in position as supplementary earthing. Earth Loop test would answer the question if you were so inclined.

TBH tho, I'd be glad of the RCD protection with those ancient BS1361 boards on overcurrent duty -without them, shocks would be extra crunchy....

[themadhippy]

with those ancient BS1361 boards on overcurrent duty -

given the proximity of the supply transformer im glad to see them instead of mcb's

[JamesF]

Hmmm. GIven that we only had two overhead cables feeding the transformer until two or three years ago, I'd guess any DNO-supplied earth would have to be hooked up to the neutral at the transformer. Would that count as TN-CS, or just TN-C?

James

[JamesF]

Actually, come to think of it the transformer is still only hooked up to two of the HT cables. They just added a third because of increasing demand along the supply.

James

[themadhippy]

Would that count as TN-CS, or just TN-C

certainly isnt TN-C,there a rare and very special beasty, most likely TNC-S.In theory the bods putting in the solar system should have given you a test certificate that should state the incoming earthing arrangements

[JamesF]

That's handy then. It says TN-CS. I'll have to look a bit more closely at the earth rod circuit now. Perhaps it isn't actually connected to anything.

James