Re: (ET) Curtis controller mod

["David Roden" <etpost drmm net>]

On 28 Apr 2016 at 10:51, Kim Petty wrote:

> I think I will end up mostly using the tractor in fieldweakened mode
> with 2 resistors in line and switching to full field voltage if I need
> it. 

I'm not a motor expert, but I think I remember reading that most motors 
are 
most efficient (I take this to mean less heat) at full field.  Normally 
you 
use field weakening as a sort of overdrive.  

That said, this may not be the case with the GE motor - it may be designed 
for use with FW.  

Maybe the motor experts here will weigh in on this.  Absent that coaching, 
I 
think I would try to run the motor at full field most of the time.

PS - If I recall right, Mark Hanson built his own controller for an ET 
years 
ago and used full field.  To get the higher top speed back (and probably 
then some), he added 2 more batteries to the motor circuit for 48v.

Robert, your Curtis setup sounds good.  I think yours is the one I 
remember 
reading about lo those many years ago.


David Roden - Akron, Ohio, USA

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