In article ,
Christian McArdle wrote:
Example - take a 3 kW immersion heater fed via 20 m of 2.5 mm^2 cable.

I'd say that is unusually long. Have you been taking lessons from
dribble?

I doubt it is excessively long in many installations. Remember that it
often has to take a circuitous route, and perhaps go up a storey or two.
Indeed, a quick estimate on the length of my immersion heater cable is
18m.

I make mine 4 metres.

--
*Procrastinate now

Dave Plowman London SW
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