(ET) Hoping To join Your Group

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ELECTRAKKERS

Hi All, This is the first time writing the group but I have been reading the many 
years of past messages for several weeks now, & I am glad to hear that Elec-Traks are alive & well. I have 5 ElecTraks, but few attachments.

My E15, named the Plywood Pony because of the plywood used to replace
much of the rotted sheet metal is in some ways my best effort to date at
restoring to usable service.

I got the E15 from a friend who has several Electraks himself. He wanted a 
large UPS & I wanted a Electrak, so we traded. It came with well used
batteries & the wiring was in poor condition. It did not take me long to
realize that I could get the beast going by doing a major upgrade to the
electric's, rather than putz with the old wiring.

I first made a PWM controller for the traction motor & got it going at least
in one direction. Then I experimented with several reversing schemes. I
eventually settled on using a manual reversing switch to steer the current
through the armature, rather than reverse the field. After many years of observation on DC motors, I am of the opinion that reversing the armature current
may extend brush life, as opposed to not. This has worked now nearly
4 years. 

The old batteries gave me about a year of service, I attribute this in part
to the fact that the traction drives efficiency is much higher using PWM,
& that peak current demands on the battery are lessened. Also, there
are no contactors which use at least some current.

With the old batteries still in place I experimented with various chargers, as
this tractor came with none at all. I found some surplus Vicor 48VDC
telecom switchers which could be adjusted down to make excellent chargers.

Eventually the batts were replaced with SAM's Club golf cart batts. They have 
been in service for 3 years now, & despite the heavy use I give them, I have yet to
ever have to water them. This Is due to the fact that because I use very little
current through any battery taps, consequently I never have had the need to 
equalize the battery bank.

The front 2 batteries have been placed side by side, transverse to the tractor.
As the original sheet metal was replaced first with plywood & eventually
with metal, I had made the front battery compartment as wide as the frame.
With the old charger gone & the batteries effectively move back several inches,
I now had space to make a better winch which resides in the front portion
of the battery compartment.

I would like to join your group, but for some reason have not been able to do
so through the traditional methods. If anyone has the time & patience to show
me how to join the group, I would be most appreciative

STEVE