[SeattleTrainGuy]

Hello all, new Guy here. Iam working on converting a 12” gauge miniature locomotive with two 48v, series wound, 7” Clark forklift traction motors (with Curtis 1209b controllers). One motor/controller on each bogie (2 drive axles and frame). E.G. each motor will separately drive its own set of axles and wheels with chain/gear reduction.

Looking for the best method to synchronize motor torque for the two motors and controllers, with one throttle control. Can anyone help with a recommendation and possible wiring diagram?

P.S. I’ve searched for master/slave setups, but found nothing related to controlling two independently mounted motors- driving separate axles...

Thanks much for any assistance you might be able to offer.

Glenn B.

 

[brian_]

Curtis does support master-slave configurations, at least of their AC controllers, intended for separate left and right wheel motors - that would work fine with the steering input set to zero, so the speeds match. But you're using DC controllers...

You can probably just wire the same throttle signal to both controllers; with the controllers taking that as a torque command, the motors would share the driving duties properly as long as one set of wheels don't slip.

 

[SeattleTrainGuy]

Brian, thanks.

Coming up with a similar question regarding setting up forward/reverse contractors.

Should I plan on adding a separate forward/reverse contractor for each motor, or, use one contractor to drive both motors?

Thanks
Tlenn

 

[remy_martian]

If your contactors are after the speed controller, you need one for each controller.

 

[brian_]

Coming up with a similar question regarding setting up forward/reverse contractors.

Should I plan on adding a separate forward/reverse contractor for each motor, or, use one contractor to drive both motors?

Those contractors switch the polarity of the motor field (stator) windings relative to the armature (rotor), so they are switching controlled current and are so inherently after the controllers. As remy_martian said, there will need to be one for each motor.

 

[SeattleTrainGuy]

Thanks for the followup. I’ll plan on using two F/R contractors. Thanks!