Re: (ET) Reversing E20 DA Motor Polarity

["Ralph G Vogan" <ralphgv CenturyTel net>]

Sorry I couldn't respond sooner, I was out of town.

Some of the differences I noticed with the new controller are;

    1. The old foot pedal used limit switches and required more travel to
change the speed of the motor.  The new setup responds much quicker to very
small movements of the foot pedal.

    2. The old system changed the resistance in series with the motor, 
which
changed the motor speed slowlly.  The solid state circuit responds almost
instantly.

       These changes make the tractor feel jumpy, the rougher the ground 
the
worse it feels.

    3. The E20 always ran faster in reverse then forward because of the
small series field winding.  You just didn't notice it because the old foot
pedal was limited to only 4 speeds in reverse.  I found it very noticable
with the solidstate controls.

       I have the foot control, and a dash control hooked up to the cruse
control button like John Briese.  The dash control is a lot smoother ride
because there is no foot pedal bounce.  I have found that I use the dash
control about 70% of the time, but the foot control is better when 
starting,
or manuvering around things.

    4. If the drive motor brushes are worn, or a brush spring has been over
heated and lost some of it's pressure, you could get jumpy action from the
motor, that could show up more in forward than reverse because of the 
series
fields reaction.

    5. If you reverse the armature leads the motor would run faster in
forward but it would slow down a lot more under a load or even climbing
small hills.

    6. I think my controller switches the field circuit for forward/reverse
control because the field draws less current.

Good luck
Ralph V
ralphgv centurytel net


Original message

 Will a member, maybe Ralph, who has experience with the electronic
controller conversion of the E20, tell me the best way to change rotation
direction on the E20 motor? The original setup of the drive motor runs best
in one direction and is kind of jumpy in the other direction. Is it OK to
run the motor with armature cables reversed so that the smooth running is 
in
forward gears? The motor now wired in accordance with supplier provided
schematic is jumpy in forward and smooth as silk in reverse. The motor was
tested before the conversion using two 12v batteries and direction of
rotation was reversed by changing either the polarity of the field (F1 & 
F2)
or the armature (A1 & S2). A comment will be appreciated. Thank you. Raymon
Ellis