Re: House power and damaging kit!!!

[Neil Fuller <neil.fuller@xxxxxxxxx>]

Yup, I had a similar problem with a H-U-G-E 12V PSU I built many years
ago to supply big 2M amateur radio linear amps.

With over 2 farads of smoothing capacitors in the thing, not only did it
blow fuses, it also blew the Bridge Rectum Fryer the first time I tried
to turn it on!!

Cheers

Neil

Keith Doxey wrote:
>
> Hi Paul
>
> > Interesting - I guess they probably do have SM PSU's. Are surges
> > etc not likely then on turning the power back on?
> >
>
> Surges do occur when power is first applied but it is the equipment
that
> causes a surge on the mains. This can cause the breakers to trip.
>
> Ever noticed that if you plug a live mains lead into a PC there is a
"pop"
> as the power supply input capacitors initially charge up?
>
> If I turn my mains supply off I can guarantee that when I turn it back
on
> the Ring Main MCB will trip due to the inrush current from all the
kit. It
> doesnt trip after a power failure as I guess the fact that every house
is
> "firing up" limits the current that can be drawn.
>
> Big power amplifiers have "soft start" circuits to limit the
inrush
> current
> to prevent fuses from blowing. A mate of mine had a 1000W amp and the
soft
> start failed, it blew the fuse everytime you tried to turn it on.
>
> Regards
>
> Keith
>
>