Cable concerns

[festive]

Ive just put an offer in on a new house, and after having a wander around i noticed what seemed to be the main supply entering the garage.

Up on the wall there seemed to be to digital electric meters, first of all, why two? The house did use electrical storage heaters as opposed to CH are they on a sep circuit or something?

Secondly, next to the meters and isolater switch is a huge SWA cable coming up from thr floor, it's got to be about 5cm in diameter, which then feeds into the biggest isolater box ive seen, okay maybe 40cm x 25cm which 'i think' fed the 2 meters im not sure i can't remember.

It just seemed very overkill for the house, nothing near the arrangement i have in my current bungalow (2 beds as opposed to 4beds) And im concerned as id like it out the way as id like to use the garage as a studio.

Any answers about why this cable/box is so huge is most appreciated. The cabling did look quite new, as did the tails and the digital meters.

 

[jondiy]

Maybe the house was previously two seperate flats!!

Maybe the DNO has graced you with 300 Amps of 3-phase hence the big switchgear !! , although without a photo its hard to tell, and it is doubtful.

A photo of it would be helpful, then people could analyse it for you.

 

[JohnD]

It used to be my house, when I retired from working in the Brinks-Mat depot I had a smelting furnace in the garage.

 

[plugwash]

i see two main possibilities

1: there was some big electrical kit installed before.
2: its the last house in a run and they just brought the main cable into your house and terminated it (they are known to do this sometimes at the ends of runs)

two seperate meters does sound a bit like the house was two flats before (very old off peak systems also use two meters but your install sounds a bit modern for that)

as always a photo would be nice.

 

[festive]

For your replies people, i shall endeavour to grab a photo, indeed it's not easy with my description. I thought it might of been 3phase, but im pretty sure i the tails from the box were red black and green not err isn't it blue for 3 phase? Anyway...ill beback!

 

[plugwash]

3 phase in old british colors is red blue and yellow phases and black neutral. in current (very recently introduced colors) its brown black and grey phases and blue neutral.

it sounds like you may have a 3 phase head but not have anything 3 phase beyond the head.

also if you have a multimeter CAREFULLY measure the voltages between the two lives from the meters (they terminate in something like consumer units right?). If you see 415V (or therabouts) it means they are on two seperate phases!

 

[jondiy]

At least you would'nt come across the 'I need to get power to my garage' dilemma!! SOunds like your garage is a major powerhouse!!!

 

[festive]

Okay, to make it clearer for all, here's a pic, and ive labelled all the bits, as you can see im intrigued about the size of Box G. My dad reckons the 2 circuits is due to the storage heaters in the house and economy 7?
Also there seems to be about 5 isolator switches herE??

All comments most welcome!

 

[Adam_151]

A and B are REC meters, A seems to be normal, and B seems to be off peak, C is the switch that brings the off peak supply in at the right time, E is an old voltage opperated ELCB, the forerunner to an RCD, G seems to be an old switch fuse.

H is some kind of REC equipment (I don't know), D is switchfuse for main supply, and G is switchfuse/single way board, I'd guess for any lights/sockets in the incommer room/garage/basement (or whatever it is)

It looks TT to me (well I can't see any REC provided earth, the main supply doesn't seem to be RCD/ELCB protected though , and while the off peak supply is ELCB protected, they haven't been recognised in the regs for 20 years, so its quite old, so it might have jammed up, and anyway with todays parallel earth paths through bonding etc, they are not too effective, so it should be replaced with an RCD

I suggest you get someone in to have a look at it

 

[festive]

Thanks for post, why two incoming feeds though and such a large cable? I dont need 2 feeds do i, as im installing Gas CH so no more storage heaters, i thought i'd only need a feed direct into one of those REC meters (they have DP isolator built in nowadays?) Then do away with ALL the other bits.

I'm guessing the feed from I then goes off to the CU am i correct?

 

[Lectrician]

Well, you have off peak.

What a mess.

TT system.

RCD for main install(H), via rec meter A.

ELCB for off peak storage rads(No longer to BS7671, and very dangerous!)(E), via rec meter B.

Two switch fuses very old, and glanded/earthed incorrectly.

Must have two fuseboards in the house somehwhere - fed from the two armours.

Switch fuse F doesn't appear to be RCD protected - oh dear.

Submains look like 60 and 100amp respectivly for off peak and peak.

Can't beleive the mess - needs sorting. ELCB needs ditching.

You need a PIR report urgently.

 

[Lectrician]

I is the INCOMMING feed from the DNO network!

 

[Spark123]

Is that a pipe clamp on SWA cable above D?

 

[Adam_151]

Certainly looks like it, 123... it's not unknown for the spur wearing element to earth SWA like this

 

[festive]

Thanks for your comments people, so to clarify are the SWA cables, the feed from street?

If so, isnt all this work undertaken by Leccy board as i thought they were responsible between supply and meter? Then contractors from tails onwards to CU etc right?