Re: (ET) controller

["Clean Power Supply" <cleanpower att net>]

 I agree that the Curtis controllers used in this manner are quite 
practical. And now I'll share my secret: I have top speed WITHOUT 
weakening the field. I use a larger motor pulley with a smaller trans. 
pulley, sized appropriately to achieve top speed with full field voltage. 
Since speed control with an electronic controller is almost 
infinite,losing the lower gearing is of no great consequence. 
 Additionally,I don't use *any* contactors,only a master disconnect 
switch. The switch on the pot is used to turn the KSI (Key Switch Input) 
on the controller on and off. A toggle switch with center off is used to 
reverse the field polarity thereby achieving motor reversal.The center off 
turns off the KSI,requiring the foot pedal to be brought back to neutral 
to restart.This prevents slamming from F to R while the motor is running 
and also gives a bit more time for the field to collapse before polarity 
reverses.I do use a varistor to help with that,though.
 Sincerely,
 Harold Zimmerman
 Clean Power Supply
 Ephrata PA
 717-859-4234
 Parts Supplier for GE Elec-Trak,New Idea & Wheel Horse Electric Tractors.

On February 10, 2011 at 4:05pm -0500, you wrote:
>I am here to tell you the answer is simply and emphatically YES.
>
>I have an E15 w/a Curtis 36V golf car controller in it. When you step on 
>the
>"go" pedal (it's an E-15, but I put a pedal on) a microswitch closes which
>energizes two contactors' coils. When the contactors close, they energize
>the field windings (full 36v across the windings) and energize the
>controller. Further motion of the pedal turns a 5k pot (a very familiar
>set-up to those of you who have messed with Curtis controllers, not to
>mention others) which increases the current from the controller through 
>the
>armature. Off you go!
>
>A simple DPDT allows reverse (an h-bridge for reversing the field winding
>current). I plowed with that set-up for two winters... worked great. 
>Buttery
>smooth! Just not much of a top speed w/o the field weakening.
>
>I have NOT put field weakening on that set-up, but it would be easy enough
>to do using relays and an original resistor card.
>
>Note that sometimes you can find Curtis 36v Sep-Ex controllers on ebay for
>short money... I have one that I intend to put in another E15 whose 
>original
>control system was badly damaged. Got it for $79 last year... looking
>forward to trying it out.
>
>Oh, speaking of which:
>http://cgi.ebay.com/4-CURTIS-PMC-SepEX-DC-MOTOR-CONTROL-24-36-VOLTS-400-AMP-/110642253704?pt=LH_DefaultDomain_0&hash=item19c2cacf88
>
>Best to all,
>
>-Max
>
>On Thu, Feb 10, 2011 at 3:00 PM, Neil Dennis <wombatt gmail com> wrote:
>
>> Just a thought, can you use a PWM type control on that motor  ?  Or 
>> change
>> to a PM motor and then PWM  ?
>>
>> wombat
>>
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>>
>
>--
>www.maxmatic.com
>
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