Re: (ET) E-15 Reverse relay Arcing

["Bob Murcek" <rmurcek geisinger edu>]

All this reverse relay misery might be another answer to the question 
someone posed a while ago about why convert to a solid-state controller! 

The diode thing can't be used in this case since the purpose of the 
reversing relay is to reverse the polarity to the field, which means no 
matter which way you put the diode across the field, the diode's going to 
be a short circuit in either forward or reverse.

Has anyone tried anything nice and complex, like back-to-back Zener 
diodes?  Or a snubber circuit?

>>> Dave & Debbie Barden <daveb seanet com> 5/2/2003 7:40:32 AM >>>
I have an E12 with this same problem.  Admittedly still unsolved.  after  
repairing the relay several times it finally fused together beyond repair. 
 
before putting in the Bill Gunn version ($20) I came across the Hosfelt 
catalog 
that had  some surplus relays of similar specs for $2.00each. I bought 6 
(they 
were subsequently stolen along with my van but that's another story).  I 
burned 
up one of those before putting in a fuse in line between the relay and the 
field.  now I just blow fuses but all the time.  On the E12 the varistor 
($4 
from Bill) is behind the lower panel cover jumping the field wires in the 
connector.  I replaced it.  A friend of mine thought putting in a diode to 
block the electrical surge of the collasping field when the motor changes 
direction would help.  It didn't.  I suspect in my case something else is 
amiss 
but I haven't found it yet.  good luck with yours!

dave
E12S in Seattle


> - Yep, the schematic shows one. I'm not sure offhand where it is located,
> but I imagine it's on the reverse relay or on a small card nearby.
> 
> Also  the E12S, E15 manual (Elec-Trak.Org) has reverse relay 
> troubleshooting
> and a service bulletin at the very end.
> 
> 
> >
> > There might be a varistor that goes across the relay to absorb the
> > sparks, or a capacitor. If so I'd bet it's blown.
> >
> 
> 
> 
>