Info about my mains supply cable route - plus other bits...

[RWhites]

Which bit of Yorkshire are you in?

I've worked on supplies like that in the past. The feeder cable is a bit like twin and earth, only it's twin without an earth, and the external sheath is much tougher than normal PVC, more like hi-tuff It looks like a 16.0mm² supply to me. The last one I saw was just outside Halifax.

The supply type is PME. Note the big yellow sticker on the bottom of the cutout Most likely a TT conversion I'd imagine.

You may have to get your meter operater involved in the supply move. The last supply Northern Powergrid moved for one of my customers, they did NOT move the meter

Funnily enough I'm just outside Halifax!

So if Northern Powergrid don't move the meter, do I need to get Scottish Power (my leccy company) to be here on the same day to move the meter??? Odd. I'm trying to do a 'plan b' in my head, but struggling to come up with a viable alternative.

Just to try to clarify the other questions in my head:

What is a submain? - Am I right in thinking this is the name given to the run of cable from switchfuse to CU?

If yes, what cable should I be looking to use? (it will be clipped to the underside of joists in a crawl space under the floor).

What is the correct method of running the tails through the house wall to the switchfuse - in terms of cable spec / protecting it etc.

 

[Chri5]

A sub main is a cable extending from the main head feed, so a house with a garbage cu and a main cu would have two sub mains.

Most switch fuses have to be in close proximity of the main head connection, less than a meter and if the main head is outside with a meter, back to back is normal.

It would be normal to run 25mm sq swa between switch fuse and cu. it's a fair lump of cable. About an inch in diameter and screw cleats are needed to hold it well.

The armour of the swa needs to be earthed. Search the forum for swa earthing for details on banjos, metal boxes, piranha nuts. Neatest is a metal clad cu, and metal clad switch fuse, glanded direct to case.

You really do need to have a design chat with the guy that will be expected to sign off the cert, each of us will have a slight tilt on product type, method of run, position of bits etc.

 

[ban-all-sheds]

a house with a garbage cu and a main cu would have two sub mains.

Don't talk rubbish.

 

[RWhites]

a house with a garbage cu and a main cu would have two sub mains.

Don't talk rubbish.

 

[RWhites]

A sub main is a cable extending from the main head feed, so a house with a garbage cu and a main cu would have two sub mains.

Most switch fuses have to be in close proximity of the main head connection, less than a meter and if the main head is outside with a meter, back to back is normal.

It would be normal to run 25mm sq swa between switch fuse and cu. it's a fair lump of cable. About an inch in diameter and screw cleats are needed to hold it well.

The armour of the swa needs to be earthed. Search the forum for swa earthing for details on banjos, metal boxes, piranha nuts. Neatest is a metal clad cu, and metal clad switch fuse, glanded direct to case.

You really do need to have a design chat with the guy that will be expected to sign off the cert, each of us will have a slight tilt on product type, method of run, position of bits etc.

That's a beast of a cable! I think I'm going to have to have a serious re-think....

I also want to just say a big thank-you to all contributors for their help and advice - much appreciated.

Cheers.
Rich.

 

[Chri5]

Proxy iPad spelling correction

 

[Chri5]

Proxy iPad spelling correction

Can't even get poxy right

 

[SUNRAY]

just looked again at the pics - is the supply cable into the bottom on the company head twin and earth????

(Or do I need new glasses??)

Yes this very normal on older overhead installations but usualy only twin with no earth

 

[RF Lighting]

Yes this very normal on older overhead installations but usualy only twin with no earth

The feeder cable is a bit like twin and earth, only it's twin without an earth

 

[LUG]

Horrible cable to use

 

[SUNRAY]

Yes this very normal on older overhead installations but usualy only twin with no earth

The feeder cable is a bit like twin and earth, only it's twin without an earth

Note to self - read every detail of the whole thread before posting.

As you say RF it was tough stuff and comes up much thicker than modern T&E, it was commonly only 7/0.044 [app 6.5 mm] which was, I think, rated around 40A at best.
There used to be such a large selection of sizes it can be hard to tell by sheath size alone, but in the pics it could be a bigger size like: 7/0.063 [14mm] or 19/0.036 [12.5mm].