22 Sep
2011
22 Sep
'11
12:52 p.m.
On Wed, Sep 21, 2011 at 3:07 PM, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
My RK07s have been well-behaved (until now, lets hope it continues). I
did have a bridge rectifer go short-circuit all ways rounf in a 3rd part
(Plessay) Unibus expansion box. The wiring between it and the mains
transformer glowed red-hot and lost all its insulation (with lots of
magix smoke), but no other damage.
And if you saw a flickering light from the rear
right corner through the
door you powered down at once....
Never had one smoke (though we did nearly set off the halon from fried
rectifier diodes on an RK07 when one of the filtering caps went zero
ohms... The blower fan runs off the mains, using the
transformer primary winding
as an autotransformer on 230V mains...
Sounds like a serious risk on your side of the pond, but here, inside small
kit we only push our electrons around half as hard. I won't say it can't
happen in the US, but ISTR mains wiring here is clad in plastic that
is rated to 600V.