(ET) Controller on eBay

[Jim Coate <jbc coate org>]

Are you referring to item #1824354828?
     http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1824354828

If so, a quick glance makes me think it is not that great a match. Yes,
you'd have to leave the field full "on" losing the highest speeds, and
then the PWM controller only gives 6 discrete speeds.

HOWEVER... I noticed that the schematic the seller posted was drawn by
Lee Hart, one of the regulars on the EV list* and a very qualified
engineer. He owns ET(s) and on-road EVs and has obviously seen this
particular controller at some point. I've taken the liberty of
forwarding him the question and will post any response (unless he lurks
on this list already?).

*The EV list seems to have been broken for a few days, otherwise I would
have thrown it out there for general discussion.


SolidTech wrote:
> OK... I know this has been discussed before, but there's a 36V motor 
> speed
> controller on eBay as well.  It is a PWM model.  I have an E-15 and it 
> has
> the separate connections for the armature and the field (to enable field
> weakening in the higher speeds).  The controller only has two 
> connections (+
> and -) for the motor.  So, to use this type of controller what happens to
> the field weakening - just not used?  And if that is the case, then is 
> the
> top speed just not as fast?  What effect would that have on the lower 
> speeds
> in terms of power production - better or worse?  Could an "overdrive" be
> added that would engage some field weakening once the highest speed was
> reached on the controller?
> 
> thoughts?
> - - joe
> E-15 in Colorado

_________
Jim Coate
1992 Chevy S10
1970's Elec-Trak
http://www.eeevee.com