Eh? But it is fused down? And even if it weren't, and 1.5 were used, the CCC doesn't change so surely it wouldn't need de-rating.ColJack said:majority of times it would be on it's own 16A or 20A breaker fed with 2.5 and isolated with a double pole switch.. no fusing down, so it should carry on in 2.5..
Softus said:I apologise - I misread your post, and was thinking that there was an FCU involved, i.e. limiting current to 13A. Sorry.
PS Sorry.
I think so.RF Lighting said:Is this any different to a twin socket spurred from a ring circuit though?
The double socket isn't rated at 26A, so it isn't ok; although I take your point that it's ok for the cable, but these loads are attached to fused plugs, so even a fault current in an appliance couldn't exceed the cable CCC.In that scenario you have a cable rated at 27A supplied by a 32A MCB, so the cable is too small for the OCPD, but as the cable only feeds a twin socket, the maximum load that can be drawn on the single 2.5mm² is 26A, which is ok.
But this load is unfused (if wired to a DP switch only) so a fault current could exceed the flex CCC.With the imm heater scenario, there may be a 20A supply to the 20A DP switch fed in 2.5mm², but as the imm heater is a fixed load of 3kW (around 13A), then the most current that can flow on the 1.5mm² flex is 13A, which is ok for the CCC of the flex.
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local