Re: Re: (ET) What was that crash?

["RJ Kanary" <rjkanary nauticom net>]

 The 'L' contactor on the E- 8, E-10 must have a propensity for that. I've
seen that happen, also. The only theory that I can offer is, since it IS a
DC system, residual magnetism CAN build up in the contactor's armature. Add
to this, a weakened restoring spring, [time and heat do take their toll],
and you do have a recipe for excitement. Remember, this contactor  'locks
in' it's own coil circuit, internally, after the armature lead contacts are
closed. Any leakage across the key switch, and you are off to the races !
      The problem is not unknown. In automatic transmissions, the use of
solenoids is increasing in numbers.These turn out to be very costly parts,
so efforts are made to return them to usable condition, after a 
transmission
failure. One of the processes used in remanufacturing these, is
demagnetizing the armatures. This is necessary, to at least have a chance 
of
predictable performance.If in the case of a PWM solenoid, the armature was
already magnetized, its movement for a given duty cycle would not conform
with what the system was designed to do.


RJ Kanary
Member TRNi  Since 1998
ASE® Certified Master Auto Technician

rjkanary nauticom net

----- Original Message -----
From: <Oasis654 aol com>
To: <ssawtelle fcc net>; <owner-elec-trak cosmos phy tufts edu>;
<elec-trak cosmos phy tufts edu>
Sent: Thursday, June 06, 2002 9:58 AM
Subject: Re: Re: (ET) What was that crash?


>
> In a message dated 6/6/02 9:35:57 AM, ssawtelle fcc net wrote:
>
> <<
>
>   When I got the thing, the safety feature that prevents it from starting
> without your foot on the pedal was already broken.  I ordered the parts 
> to
> fix it, but never got around to it. (Those round tuits are hard to find 
> --
> mine are all square!)  Now, it seems something has shorted and turned the
> motor on even though the key switch is off.
>
>
>   Question:  Is this likely to be a bum relay or just the key switch?
This
> happened on a damp night, although the E-10 is under cover.
>
> >>
>
> hi all, i had this same thing happen while working on the e10 and the 
> wind
> blew the hood down suddenly and started the traction motor.  the key was
off
> too.  problem was not the key, but one of the relays that got jarred when
the
> hood slammed shut.  it got fixed by someone else so cant say exactly 
> which
> relay it was, but there aren't many on the e10.  good luck, jon k
>