New supply - choosing a supplier to fit the meter

[d000hg]

We have a new supply booked to be fitted this week, everything is ready for them to come and install down to their fuse in the new box.

The guy who came out from Northern PowerGrid explained that the new supplier then comes and pulls the fuse, installs their meter and replaces the fuse, putting new seals on.
He advised us that getting a master cut-out installed at the same time is a good option as it means our electrician can then connect to the meter without having to get anyone out to disconnect it again.

He said some suppliers will do this for free, others will charge. My inclination is to get one of the big suppliers as our first supplier, then switch later once everything is all installed and running, any recommendations on who?

When he talked about a cut-out, what exactly does that look like and where does it go - between supply and meter, or between meter and fuse-box? I'm not doing any of this myself but I like to know what it should look like so I can check they've done what was agreed.

 

[flameport]

The cutout is already there - it's the thing with the fuse in it.

Meter operator may provide a 2 pole isolator, usually something like this: https://www.toolstation.com/wylex-2-pole-isolator-switch-with-enclosure/p55771

If they don't supply one, you could buy one yourself and have them connect to it.

 

[oldbutnotdead]

BG fitted one for free, no questions.
Toolstation have a 30 day return policy I think so best bet may be buy yourself one, when meter bloke arrives ask him if he's installing an isolator after the meter- if he is, great (take yours back for a refund), if not then produce yours & ask nicely if he wouldn't mind putting it in while he's there

 

[d000hg]

My apologies you're absolutely right, I keep getting these terms mixed up.

Exactly - the powergrid guy told us some suppliers might fit an isolator for an extra £100 when it costs far less. I hadn't realised they could connect to something I provided, where does this fit... before or after the meter?

 

[flameport]

After - in the same place a consumer unit would be connected.
If you supply one yourself, it's no different from them connecting your consumer unit to the meter - it's the same main switch just in a smaller separate box.
You may need to supply the tails for it.

 

[d000hg]

I think the point is, we don't have the consumer unit yet. We had expected we'd get the supply fitted this week, then get the meter added, then wire the consumer unit a bit later. That's WHY we want an isolator, so the electrician can install the consumer unit against an active supply. At least that's my understanding what the electrician said, and I think the powergrid guy said the same.

One other question; what's the difference between the sort of deal you posted, and a rotary one e.g. https://www.screwfix.com/p/british-general-cprsd463-4-pole-rotary-isolator-switch-63a/8536r
I can see the amperage is lower so is this designed to isolate a single circuit after the consumer unit, whereas what you posted is to isolate the entire unit?

 

[RF Lighting]

You need to use an isolator rated for 100A. That rotary isolator will be near impossible to terminate 25mm² tails into. It is 4 poles and you only need two. It does not have any strain relief for the tails, and you can not work on the outgoing side of the isolator without exposing the live incoming side.

The isolator flameport has linked to is absolutely the correct device you require

 

[d000hg]

You need to use an isolator rated for 100A. That rotary isolator will be near impossible to terminate 25mm² tails into. It is 4 poles and you only need two. It does not have any strain relief for the tails, and you can not work on the outgoing side of the isolator without exposing the live incoming side.

The isolator flameport has linked to is absolutely the correct device you require

A lot of that went over my head (I don't know what poles are for a start) but thanks - it's the wrong thing for the job, that's clear. What ARE the rotary ones for?

 

[davelx]

A lot of that went over my head (I don't know what poles are for a start) but thanks - it's the wrong thing for the job, that's clear. What ARE the rotary ones for?

Aircon, EV chargers, swimming pool plant, spa baths, machine tools etc.

 

[ericmark]

You can see at the bottom there is a part which can be removed to access outlet terminals without the need to remove whole cover so it can be locked off and safely worked on, where the other one all terminals would be exposed so you would still need to draw the fuse to connect to isolator.

 

[d000hg]

You can see at the bottom there is a part which can be removed to access outlet terminals without the need to remove whole cover so it can be locked off and safely worked on, where the other one all terminals would be exposed so you would still need to draw the fuse to connect to isolator.

Cheers for that. So in my scenario, I forgot to mention that the supply and meter are being installed in an external wall-mounted box, we're then taking an armoured cable to the actual consumer unit inside the building. So I would want a unit like above specifically, so it can be mounted directly into the box?

 

[ericmark]

Inside a box that isolator will be fine.

 

[oldbutnotdead]

You'll not be able to terminate SWA directly to that isolator- make sure there's room for an adaptable box or similar (your electrician will then gland the SWA to the adaptable box, probably take phase and neutral straight through to the isolator and connect earth and cable armour via Henley block or similar to the DNO earth)

 

[bernardgreen]

A convenient and compact way to bring SWA into an enclosure that will not take a gland ( in this case a plastic consumer unit )

Fit the die cast box to the end of the SWA leaving the cores and inner sheath long enough to reach the terminals in the enclosure. Then thread the cores and sheath into the enclosure before fitting the box to the wall.

 

[d000hg]

I didn't really understand those last two replies as I don't know the acronyms.
I think you're talking about problems feeding the armoured cable into the isolator from the context, as far as I know the electrician had planned for that but thanks, I could see people getting caught out.