Power to detached garage when no spare way in house CU?

[Sponge]

I've just got home from work and after my tea will post some pictures to illustrate my situation.

But to start with - yes, the electrician wasn't willing to re-connect the garage.

I was quoted for (and probably paid for) a 10-way CU, but it appears there was only space for a 8-way? (Picture to follow.)

Untitled

• Sponge
• 21 Apr 2014
• 1

I'm not sure I have a picture of what was in the garage (I've now ripped it out) but it was an old, brown 'switch' with ceramic/wire fuse in it. (Apologies for the poor terminology.)

Unfortunately, I'm going to have a similar problem when I come to want lights/sockets in the loft - he's run a cable from CU cupboard to loft, but I don't know how/where it'll be connected to the supply.

EDIT: I'll add pictures to the original post.

 

[winston1]

Why has the "socket below consumer unit" got its own MCB. Surely this could go on one of the other socket circuits thus releasing a spare way for the garage.

Regarding the loft there is no reason why the socket(s) cannot be on the upstairs socket circuit and the lights on the upstairs lighting circuit.

 

[Sponge]

I think that might be a 'left-over' from when the rewire was being performed. The house electrics were deactivated and he installed one socket from which all power came for tools, etc.

When I was taking the photo it did occur to me that it could be better utilised now the rewire is complete. That may have been his intention, were I to call him back. But he never divulged that information.

So, without having to touch the CU, I could remove the double socket and connect the cable from the garage to it?

If I do that, does it remove the need for a CU in the garage? Just terminate with a socket and FCU off that for a light?

Although, ideally I'd like two, maybe three doubles along the wall. They're not all going to be used at the same time. Just for convenience. No heaters, or other high-current applicances. (E.g. One socket near entrance for lawnmower, one in middle for a power-tool/battery charger, one at far end for decking LEDs.)

 

[JohnW2]

So, without having to touch the CU, I could remove the double socket and connect the cable from the garage to it?

It looks/sounds as if that might be an option. What is the rating of that MCB - I can't quite read it on the photo.

If I do that, does it remove the need for a CU in the garage? Just terminate with a socket and FCU off that for a light?

That is also a possibility.

Kind Regards, John

 

[Sponge]

So, without having to touch the CU, I could remove the double socket and connect the cable from the garage to it?

It looks/sounds as if that might be an option. What is the rating of that MCB - I can't quite read it on the photo.

If I do that, does it remove the need for a CU in the garage? Just terminate with a socket and FCU off that for a light?

That is also a possibility.

Kind Regards, John

16A

 

[JohnW2]

It looks/sounds as if that might be an option. What is the rating of that MCB - I can't quite read it on the photo.

16A

If 16A is enough for your garage, then that would be OK. If it's wired in 2.5mm² cable, you could probably upgrade the MCB to 20A, but it could be 1.5mm², in which case you would be stuck with the 16A.

Kind Regards, John

 

[ekmdgrf]

Why is the double socket underneath the CU on it's own circuit? I would moved those onto the downstairs or IT circuit and then you have a spare slot. Assuming of course that the cables for these circuits run near the double socket...

 

[JohnW2]

Why is the double socket underneath the CU on it's own circuit? I would moved those onto the downstairs or IT circuit and then you have a spare slot. Assuming of course that the cables for these circuits run near the double socket...

That's essentially what we have been discussing in the last few posts It sounds as if that one socket is not actually required, so it represents a 'spare way' that could be used for the OP's garage supply.

Kind Regards, John

 

[Sponge]

Giving it some more thought, I do actually need a socket in that cupboard to power my telephone and BT Home Hub which sit above it. That socket really needs to be added to the downstairs ring, like suggested, freeing up a MCB for the garage.

 

[JohnW2]

Giving it some more thought, I do actually need a socket in that cupboard to power my telephone and BT Home Hub which sit above it. That socket really needs to be added to the downstairs ring, like suggested, freeing up a MCB for the garage.

No real need to do that - you could leave the socket as it is and take your garage supply from the (connections of the) socket.

Kind Regards, John

 

[Aragorn84]

Whats with the weird three module RCD on the left side of the board?

 

[EFLImpudence]

Crabtree Starbreaker.

The line supply is by plugs into the bus-bar

so the bus-bar has to have a (module wide) space which the first RCD bridges.

 

[AndyPRK]

Normal for a Crabtree.

You don't end up with many Mcbs though!

 

[Sponge]

It looks/sounds as if that might be an option. What is the rating of that MCB - I can't quite read it on the photo.

16A

If 16A is enough for your garage, then that would be OK. If it's wired in 2.5mm² cable, you could probably upgrade the MCB to 20A, but it could be 1.5mm², in which case you would be stuck with the 16A.

Kind Regards, John

The garage cable is marked as 2x2.5mm + 1.5mm.

So, it looks like a plan could be:

* Upgrade MCB to 20A.
* Connect garage cable (2.5 T+E) to socket underneath CU.
* Cable into garage feeds 2 or 3 double sockets. (Radial circuit).
* FCU off one of the sockets for lights.

Oh, I didn't mention there'd be a 130W fridge freezer in there too. That'll be the only device on 24/7. As I said earlier, the only other equipment being used will be lawnmower, power tools, charging batteries and LED decking lights - and not all at the same time.

 

[JohnW2]

If 16A is enough for your garage, then that would be OK. If it's wired in 2.5mm² cable, you could probably upgrade the MCB to 20A, but it could be 1.5mm², in which case you would be stuck with the 16A.

The garage cable is marked as 2x2.5mm + 1.5mm.

In that case, as I said, you could probably upgrade the MCB to 20A, if you didn't think that 16A was enough for you. However, if 16A is enough, then sticking with the 16A MCB would be fine.

Kind Regards, John