Did you clean the carbon off of the armature? If the build up is bad enough you 
can have a frame short.

Sent from my iPhone

> On Oct 29, 2017, at 10:58 PM, Mike Nickerson via EV <ev@lists.evdl.org> wrote:
> 
> Hello everyone,
> 
> I've owned a long-time conversion for the last 7 years or so.  It is a
> medium performance conversion with ThunderSky cells (still going!), Kelly
> KDHD Series Controller and ADC FB1-4001-A series DC motor.  You can see its
> history at:  www.evalbum.com/2778
> 
> I'm having a performance problem with the car at low speeds, and trying to
> figure out whether it's the motor or the controller.  The symptoms are:
> 
>  -  Very sluggish acceleration at low motor speeds.
>  -  Almost no voltage droop from the batteries while having the sluggish
> acceleration (Low battery amps, as expected).
>  -  Better acceleration at motor speeds above 3000 rpm.
>  -  Good battery amps (60-70A) when driving at highway speeds.  Normal
> performance when operating at battery voltage.
> 
> If I can get to highway speeds, the car does fine, but starting out in 1st
> gear to get started is excruciating.  I think my 0-60 time is probably 50-60
> seconds.  Without a clutch, it takes about 5 seconds between shifts for the
> motor to spin down the 1000 rpm to match the transmission.  A little less if
> I abuse the synchros.
> 
> From this, I'm sure that my amps, at low voltage, when the motor is turning
> slowly, are limited for some reason.  I'm not sure if the controller isn't
> providing the amps, or the motor isn't drawing them.  The controller is
> supposedly rated for 1000A, but it's never done that.  However, it always
> had enough before to accelerate a little better than the original gas car.
> 
> I did check the brushes and they were in sad shape.  The ADC motor has 4
> pairs of brushes, on two windings.  On one winding, the left side on both
> brushes was mostly shot.  On one brush, the copper braids were completely
> gone.  On the second brush, the copper braids were nearly gone, just a few
> strands of copper left.
> 
> The brushes have been replaced, shaped and run-in for about 20 hours now.
> I'm running the motor at about 1500 rpm with no load (transmission connected
> but out of gear).
> 
> Performance is a little better, but still not right.  I still have another
> problem.
> 
> My thoughts:
> 
>  -  Is it possible that the brushes aren't full seated yet?  Could that
> cause this kind of problem?
>  -  What can I do to put an artificial load on the controller to see how
> many motor amps it's providing?  
>  -  I don't have instrumentation on the motor amps right now.  Is there an
> easy way to do that?
>  -  Is there an easy way to provide power to the motor while under load and
> the car is moving?  I would have to go to a shop to have the motor pulled to
> test it outside the car.
>  -  Any other motor checks I should do?
> 
> Any other thoughts anyone has?  Any suggestions on the tests above to
> isolate the problem?
> 
> Thanks in advance for any help.
> 
> Mike
> 
> 
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
> 

_______________________________________________
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
http://lists.evdl.org/listinfo.cgi/ev-evdl.org
Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)

Reply via email to