Electrical regs question - adding a socket to a fused spur.

[Steve S]

I have a radial circuit, protected by a 16A MCB that is used for the following:

CH (boiler, pump, valves, controller) via a FCU (3A) Immersion heater, no FCU, just a switch

I would like to add a single socket to power a wireless repeater. This thing requires a 13A socket for its wall-wart, and no other socket is within reach. I would take it from the fused side of the FCU. The current (no pun intended) 3A fuse would be fine.

Is such a thing permissible?

TIA,

Steve S

[Sparks]

I think so, but it would be better to connect to the input of the spur (Or place a junction box on the cable between the spur and the consumer unit, and connect to that), then you have a socket that wont blow a fuse if something bigger was plugged in to it at a later date (and take out the heating system!)

Sparks...

[Steve S]

Thanks for that. Good point about taking the heating out. The thing that worries me about having a socket on the immersion heater/CH radial is the mixed use aspect. Would someone coming later realise that they need to throw the CH MCB to isolate that socket? Perhaps clear labelling at both socket and in the CU might be sufficient?

Steve S

[jim_in_sussex]

doubt very much that a 13A socket complies with regs for at least 2 reasons (1) circuit load - a 13A socket is normally assumed to require a 20A spur or 32A ring that + your heating load & your circuit is overloaded (2) under diversity you can't average down a heating load.

One option is to consider using 2 amp unswitched round pin sockets - eg see

- stock item no MK K770. You'd need to feed this through a 2A fused spur, but that might keep you within your circuit maximum load & prevent any future misuse of the socket. You'd have to find an adapter to go 13A to 2A or change the plug on your router.

Even so it doesn't feel entirely satisfactory & personally I'd look hard to see if it really couldn't be hooked into a 'proper' 32A ring.

HTH

[Steve S]

A 13A -> 2A adapter sounds horrible. Looks like I'll have to find a different solution.

Thanks anyway.

Steve S

[Mike Harrison]

How about putting a fused spur unit and the 13a socket in one of those double-unit back-boxes, so the socket had its own fuse, say 2 or 5A, suitably labelled of course. Can't see why this wouldn't be OK from the technical or safety point of view, don't know about what the regs say. This would certainly better than some 2A-13A adapter arrangement being used on a plug-in wall-wart (I'm assuming it's the type with an integral plug).

[jim_in_sussex]

not utterly horrible - somewhere there's probably one of those multi-way travellers' adapters which will do this job.

or just change the plug on the router as it's surely not going to move around much?

[Sparks]

Quite, I expect the repeaters plug is a wall wart, not a normal 13A plug.

You could make sure the cable is at least 2.5mm, then uprate the MCB to 20A, then replace the switch on the immersion with a 13A FCU, then connect the new socket as I suggested before - this would then be a pukka radial.

Assuming the cable is OK, then it isn't much work, and little cost.

Personally I would label the socket on the front with "Part of the CH Circuit" or whatever I have labelled all my hidden sockets with the circuit number (A3 for example, means CU A, CCT 3) but to be honest, you would have to be a bit incompetent to just turn off 1 circuit and assume it has isolated a particular socket - I would always test it before touching anything unless it is my house, and I know what is what!

Sparks...

[Mike the Unshavable]

"Steve S" writed in news:_A7If.19775$wl.5107 @text.news.blueyonder.co.uk:

Or a Europlug / Schuko socket perhaps, difficult to source in the UK, plugs are easier to find though, ussuly on the end of a '8' plug for a low power appliance.