On Tue, 15 May 2018 06:28:17 -0700 (PDT), wrote:

On Tuesday, 15 May 2018 13:01:12 UTC+1, Clive Arthur wrote:
On 15/05/2018 11:58, Martin Brown wrote:
On 15/05/2018 11:17, Dave Plowman (News) wrote:

snipped

Despite being rated at 13 amps, most sockets and plugs aren't happy to
carry that for very long periods. They are a domestic connector and
really
for intermittent use at full capacity. As with a kettle or washing
machine
etc. Hence things like 13 amp water heaters normally not plugged in, but
hard wired. Same sort of thing with storage rads.

Indeed. 3kW is pushing it on a standard plug and socket for a near
continuous load. They are fine for intermittent loads like kettles.

ISTR there is a revision that recommends no portable appliances with
load 2.4kW due to the fragile nature of nominally 13A plug and sockets.

I can't see anything official (and I didn't try that hard) but a
supporting data point is fan heaters. Usually 2kW max, sometimes a
little more, but I've not seen 3kW.

Cheers

You've not done much looking then.

They can be found, I have a few. 2kW isn't enough for an average room
in winter.

3kW are around but can be expensive, the cheaper end of the range are
festooned with noisy and sticking fans.


I tend to wonder if the reason that there are not so many is because
of the thermal overload/ plastic shell combination.

I have overloads trip farlt often, in obstacle free surroundings. They
have a limited trip life too. After half a dozen trip events, the
springiness of the trip seems to go, preventing the fan heater working
permanently.


I dropped a 250 degree thermal fuse across one, this blew also.

I might have to do some checks to see if a higher rating is practical.

AB