brandon wrote: ↑Tue May 04, 2021 5:29 pm
I have a not so hypothetical question based on the discussion of series vs parallel, slipping and # of controllers.
If two motors were being used on a single truck, and both axles were chained together such that both motors and both axles moved together or not at all, what would be the best way to wire motors and with how many controllers?
1) Series with 1 controller
2) Series with 2 controllers
3) Parallel with 1 controllers
4) Parallel with 2 controllers
5) Don't do this
6) Other?
Iam not an expert on electric power by any means, but have been told that running two motors on one truck, with one controller is possible, if the controller is configured for that. I think I am correct in that 4QD controllers will do that also, if the motors are within the 4QD power range. Some commercially available programmable controllers can also do that as well.however most controllers with this capability are built for large EV road capable vehicles. So likely outside the size and price range for most live steamers.
Also, I think I am correct in saying typical 7.5” ga electric locos mostly all have individual chain drive from motor to axle. no trucks, that I am aware of, have two motors on a truck, one for each wheel, with both axles chained together.
I have seen a design where two motors mounted side by side, drive a single drive axle, leading to a powered truck. However, that is a different configuration that you describe.
What people have generally advised me is that similar motors on the same truck may turn at slightly different speeds, but, the weaker, or slower of the two, will compensate for the speed difference by operating a little bit faster, essentially matching the speed of the other... this may be the best answer to your question.
I’ll know more in a month or two when I get my center cab finished. It will have two forklift traction motors, with separate controllers, one for each hood end. I plan to test dual motor operating capacity to see how they work in tandem.
Glenn