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The devil's in the details, or the dodgy wiring !
Supporting Member
Apr 27, 2015
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Preston, Lancashire
I seem to remember being told at either a tech talk or something similar that there was a maximum rating for a fixed connected appliance that could be plugged in on a 13a socket.

I know a 13a socket is 3kw but in my mind I've got 2.2kw as a maximum.

I've tried looking in the BBB and OSG buy can't seem to find any regulation.

This is for a kitchen I've been asked to do where the "designer" has said an oven and microwave can go on the same socket.

I've read the manufacturers instructions and it says it should be a spur unit on the oven, but the microwave comes with a plug.

I would never put 2 ovens onto a single double socket but am I right with the 2.2kw max load before it having to be a dedicated circuit and if so can anyone tell me where it states that.

Ta very much ly.
Normally the maximum load for a 2G socket is 20A

What is the rating of the microwave ?

I think the 2kw or over is an old wives tale too - BUT I wouldn’t go putting too many 2 kw items on the same circuit
Appendix 15 states cookers, ovens and hobs with a power rating above 2kw should be connected to their own circuits, this is informative and not a Regulation.
You are right to be concerned - the actual detail is in the relevant BS but as I am retired I no longer have access have longer to the BS library to give to give you the document niumber.

The current requiremnt is that if the appliance has been approved for connection by a BS 1363 - 13A plugtop then it must be supplied with a BS 1363 plugtop pre-attached by the manufacturer as in the case of the microwave.

If the oven was approved for connection by a BS 1363 - 13A plug top it must have the plugtop attached. If it does not have any kind of plugtop attached it is a hard wired appliance requiring connectiuon unit.. This is the same for all CE appliances so it would have some kind of plugtop attached if approved.

In terms of practical application - 3kw immersion heaters used to be connected by a 15A round pin plug top to a socket adjacent to the tank. Obviously this was the replaced by the BS 1363 - 13A plug top but these could not sustain the constant 3kw load and tended to burn out at the pins. The connection requiremnt was then changed to a 20A DP Sw or joint box.