Will my garage handle my planned usage?

[littlespark]

As it’s a spur, and then having other things off it, it needs fused down to 13A.

It doesn’t actually conform to regulations as it stands.

But that can be solved by adding a fuse in the grid switch where the blank is.

Highly recommend getting an electrician to do that as they are notoriously difficult to work on.

 

[timhoward]

I'm not quite so sure the garage arrangements break the regs on their own, after all an unfused spur to one double socket in the garage would be allowed, with total potential current draw of 2 x 13A (26A), and there's currently a 20A limit (5A + 15A will blow eventually!).

I'm assuming that the ring comes both in and out of that grid switch, with each 20A DP isolator on the ring, feeding an FCU near each appliance.

Good old 433.1.204 says
"if under the intended conditions of use the load current in any part of the circuit is unlikely to exceed for long periods the current carrying capacity (Iz) of the cable"

My main concern is that having a few appliances on could get close to the load current exceeding the CCC of the cable, depending too on how the cables are run. Especially in the short length's behind that switch.

Regarding the garage - I had exactly the same idea of sticking a 13A module in that grid switch if there's no practical way to improve the arrangements.

 

[littlespark]

But it’s not one double socket on the end of the cable… it’s an old fuse board. No idea what size of fuse wire is in that 15A and 5A carrier….

I stand by what I said.

Change the garage fuse board to a double socket…. That’s ok.

Then have everything come off extension leads.