Sean Alcorn - Avion Sydney wrote:

> But seriously though, if the US is running at 7mA and we use 30mA and
> still see trips on refrigeration equipment, does it come down to our
> dirty power that Roman already pointed out? Or is this simply due to
> inherent operating characteristics of refrigeration equipment? I am
> curious if they run refrigeration compressors through protected
> circuits without nuisance trips in the US.


I think with refrigerators the motors draw a
very heavy start current and the motor is submerged
in an earthed can (compressor) with liquid freon
etc as a dialectric between the motor power and
the earthed can. Add the obvious contact arcing
etc.

One point with the "dirty power" 240vac as I have
mentioned before in the light bulb thread is that
with 240vac you get MUCH bigger inrush currents
into cold light globes, water heaters and stalled
motors etc compared to 120vac mains.

My lights here dim and brighten at many times
during the night sometimes subtle and sometimes
quite nastily. I also live near a steelworks and
copper smelter, and yes the i'm on the other side
of where the power comes from. :o)
-Roman

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