Installing isolator on tails

[Donkmeister]

As I'll be rewiring the house soon (BC notified, Part P, testing and certification discussed etc etc)

So, spoke to my electricity company regarding having an isolator installed so I wouldn't need to go anywhere near the service fuse (exposed contacts, legal property of REC etc etc)

They don't actually do them in my area, although they said it is quite unusual and do fit them in most areas.

However, they are happy to come round and pull the fuse in the morning, then reconnect it in the afternoon, me fitting an isolator between meter and CU in the meantime.

I've not actually seen one of these isolators, and can't find anything that appears to be designed purely for this purpose. I was expecting something that looks like a Henley block with a big switch on it.

So is it simply a matter of taking a standard 100A DP isolator (i.e. one that might more commonly be seen in a CU) and putting it in an enclosure?

 

[GaryMo]

Yes, you basically want a BS EN 60947-3 isolator in a 2 way enclosure.
A Wylex Rec2 is what you need, or similar.

 

[bongos]

yes. You would get an enclosure & main switch.

It will also help if you have your new 25mm tails between the meter and isolator and 16mm main earth ready for them to connect when they replace the service fuse.

 

[RF Lighting]

Why not screw your isolator to the wall with the supply tails already connected, so when the DNO turn up they can just connect the tails straight away saving them a return visit.

 

[Donkmeister]

Ah, not a bad idea... Only a tenner's worth of cable in it, seems a shame to pull them out though! Perhaps I can get some big bull-dog clips and make some jump-leads

The tails from meter to CU appear to have been replaced when the house was rewired in 1998. Phase and neutral are both in 25mm, and earth is in 16mm, no more than a 6-foot run.

Tails from incoming fuse to meter look older, but are grey PVC insulated. Phase and neutral are in 16mm, earth in 16mm. Entire length of this run is ~6 inches!

 

[TicklyT]

... Perhaps I can get some big bull-dog clips and make some jump-leads

I tried using some old meter tails as jump leads, but they aren't flexible enough. Connect the clips to one battery, and when you turn round to connect to the other one, the cable pulls the clips off the first battery, and the flying clips catch you on the back of the neck

 

[Roo]

25mm may not be ideal for jump leads but I've used it as a tow rope when I got my van stuck once.

 

[kwikfix328]

When Scottish Power fitted a new Isolator and meter to my house in April '08 it looked like this:

New meter and Isolation switch

• kwikfix328
• 19 May 2008
• 3

Just a shot of my electrical supply cupboard. You can see i have had a new meter fitted along...

 

[ban-all-sheds]

So is it simply a matter of taking a standard 100A DP isolator (i.e. one that might more commonly be seen in a CU) and putting it in an enclosure?

You can, but someone (I think it's MEM??) make a purpose designed unit with a sliding access panel over the outgoing terminals so that once it's installed you need never remove the cover and thus expose the incoming terminals...

 

[JohnD]

You can, but someone (I think it's MEM??).

You are correct

However it is quite a narrow enclosure, I think the wider ones have more resistance to twisting strain from great thick tails. I would put cleats or clips on the tails close to the enclosure to prevent it being tugged about

Here's one I prepared earlier:

View media item 820

 

[RF Lighting]

I'll be rewiring the house soon

the house was rewired in 1998.

Does it really need rewiring after just 10 years?

 

[Adam_151]

Perhaps I can get some big bull-dog clips and make some jump-leads

What CSA are kwik fit's value jump leads these days, I'm sure I've seen some that look like no more than 16mm²!

We have got a set of HGV ones, either 50mm² or 70mm², of course much more flexible cable than tails, but they actually look suitable for the job, I'd be worried about kwik fit ones melting

 

[RF Lighting]

I've got some heavy duty ones.

They are 35.0mm² tri-rated singles

I have jump started my van with 10.0mm² earth before.

Needs must and all that

 

[ban-all-sheds]

I have jump started my van with 10.0mm² earth before.

When it was done did you think "I wish this stuff was as flexible as this all the time....."?