On 16/03/2012 15:54, js.b1 wrote:
On Mar 16, 1:51 pm, wrote:
No idea if a fridge/freezer inrush mandates 13A over 10A or 7A;
standard fuse sizes are 3A 5A 13A. A lot of cheap consumer products
seem to be using internal components as the fuse :-)

Inrush of around 3x running current would give in the region of an amp
on a modern domestic appliance. Plug fuses don't seem to fussed about
motor startup current in practice, perhaps partly because these fuses
are mostly rated at well above motor rated i anyway.

Is it that low on all of them?

I would have expected it to be much larger on a fridge due to the
induction motor in the compressor. 5 to 9 times nominal is the range for
inrush on that sort of motor IIRC.

So even a couple amp normal draw, could suck 18A on startup.

I did blow a 5A fuse on a modern Bosch larder freezer.
The fuse was in a 1.2m 1.5mm extension lead used to supply it
overnight, and it blew sometime the following morning. The manual does
warn to only use a 13A fuse, so perhaps significant stall is expected
at some point. The 5A fuse might had been bouncing in boxes of screws
for a couple of decades.


--
Cheers,

John.

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