I know a little about many things. :) What you propose might not be very kind to the motor. Overhead cranes and GE Tractors were configured that way for a reason.

         Nailing the armature with max voltage and amperage shortly after armature rotation starts has a good chance of releasing very expensive smoke. :(

          PWM controls were likely configured with that in mind.

RJ

One of the nice things about modern controllers like the one that Jim Coate offers is that the big "toaster" resistors can be eliminated. They will get noticeably hot if you are doing lots of start/stop back-and-forth driving such as plowing snow off to the side of a driveway, and that heat represents wasted battery capacity.

There might not be sufficient time to install such a controller before the snow flies this fall, so I'm wonderng about a way to eliminate at least some of that waste.  The idea would be to effectively delete the 2A contactor, letting the 1A contactor short out both of the big toaster elements in series.  That means the tractor would start up in 1st speed with both elements in series with the motor and would then go directly to the 3rd speed (no toasters). Has anyone tried that, perhaps in the context of a bad 2A contactor?

I think it could be done right at the toaster by simply moving the #7 wire from the toaster's center terminal to the right terminal, where wire #8 attaches.

Of course, there are lots of other advantages to a new controller...

Larry Chace, Ithaca, NY  E15 and I-5

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