[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: (ET) High current in reverse - E20
Steve, Chris,
I had also the same issue. On my CC E20 reverse started to
pull too much current. Turned out I was loosing the field
in reverse. It was also those diodes powering the
fields and I had noticed a bad varistor at the same time.
Replaced varistor and diodes (also with 6A rectifier
version from radio shack) ... works fine ever since
I agree with chris, I'd guess these diodes are stressed
quite a bit from the spikes that occurr when breaking the
armature current and if the varistor is bad in addition then
they probably give after a couple of years.
My other E20 (a BA model) had one of these diodes bad as
well when I got it.
Markus
> -----Original Message-----
> From: elec-trak-bounces cosmos phy tufts edu
> [mailto:elec-trak-bounces cosmos phy tufts edu] On Behalf Of
> Chris Zach
> Sent: Sonntag, 6. Februar 2005 22:05
> To: SteveS
> Cc: elec-trak
> Subject: Re: (ET) High current in reverse - E20
>
>
> I don't know, but the diodes on my card#4 did the exact same thing a
> year or so back. I think the diodes are a little small, and
> that coupled
> with the fact that they're 35 years old might have done the trick. My
> varistor is intact, so it wasn't that.
>
> I replaced them with nice big quality Radio shack diodes and
> haven't had
> a problem since.
>
>
> > Anyway, any idea why would these diodes and/or traces
> fail? Could it
> > have been the varistor being out of circuit?
>
>
> _______________________________________________
> Elec-trak mailing list
> Elec-trak cosmos phy tufts edu
> https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak
>