[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: (ET) Pulsing

Brushes should move easily. If they bind up things will not work. You can sand them down a bit to make them fit easier if they are tight.
The usual sellers here have brush kits and such for the motors. As for the commutator, check to see if one of the bars is high or low or open but if one brush was stuck then even a slightly low bar would do it. I just clean up the bars with fine sandpaper and try not to be too concerned about them exactly. 

C


On 9/4/2024 12:09 PM, Rob Brockway via Elec-trak wrote:

  Ok,
I had time to work on the tractor over the long weekend.  I found I had voltage at the 
motor terminals but the E20 motor was not spinning consistently.  This made me think the 
motor was the problem.  I temporarily set up an E-12 motor on the floor and swapped over 
the wiring.  The E12 ran fine with no load.
I pulled the motor out and did some testing tonight.  I did a 4 point resistance test.  Years ago I got 
approx. .07 ohms.  Tonight I got .08 ohms in most shaft positions but as high as .58 in one position.  I 
think that is where the pulsing came from and the failure to start sometimes.  The commutator is 
grooved.  One brush feels good.  The other does not feel like it slides in and out smoothly.  I 
believe I have a new set of brushes on the shelf.
Any tips for what to look for in the brush holder and how it should feel?  Is 
it possible to find a replacement brush holder?  I can turn the commutator on 
my lathe but how critical is it to undercut the commutator?
If I have problems repairing, any recommendations for a replacement motor such 
as a Motenergy ME0909/1906?
  Thanks,
Rob Brockway

     On Wednesday, August 14, 2024 at 04:04:58 PM EDT, Rob Brockway via 
Elec-trak <elec-trak cosmos phy tufts edu> wrote:
I have a Curtis 1204 set up with traditional contactors feeding an E20 motor.  Under high load conditions climbing a hill or when the battery is 50%-70% drained I am getting a pulsation perhaps 2-5 hz.  You can feel it and see it on the load meter.  I have not had time to make diagnostic measurements yet.  Has anyone run into this before?  The consistent pulse makes me think it is the controller.  The controller is 16-20 years old and I am wondering if it may be failing.  Any input is appreciated. 
Rob Brockway
-------------- next part --------------
An HTML attachment was scrubbed...
URL: 
<http://cosmos.phy.tufts.edu/mhonarc/elec-trak/attachments/20240814/23f817e1/attachment.htm>
_______________________________________________
Elec-trak mailing list
Elec-trak cosmos phy tufts edu
https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak
-------------- next part -------------- 
An HTML attachment was scrubbed...
URL: 
<http://cosmos.phy.tufts.edu/mhonarc/elec-trak/attachments/20240904/753f1236/attachment.htm>
_______________________________________________
Elec-trak mailing list
Elec-trak cosmos phy tufts edu
https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak