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Electronics => Electronics => Topic started by: maceliz on July 26, 2014, 09:19:58 PM

Title: Problems running motors with sabertooth
Post by: maceliz on July 26, 2014, 09:19:58 PM
I'm running two 24V 35amp motors with a Sabertooth Dual 25A 6V-24V Regenerative Motor Driver connected to a remote controller and it is working fine but after some minutes the motors stop, my assumption is the wiring is getting to hot as I can feel it and are not allowing the current to flow but I'm not sure.

If I wait some seconds the motors work fine again.

I'm using 12 gauges wires and planning to change it for 8 gauge wires?

Do you think I'm doing the right assumption or might be something different?

Thanks
Title: Re: Problems running motors with sabertooth
Post by: Tommy on July 27, 2014, 03:12:36 AM
Quote
I'm running two 24V 35amp motors with a Sabertooth Dual 25A
maceliz, something seems wrong with the above line(using 25A drive with 35A motor?)
do you have a model or part number for the motors your using?

Tommy   
Title: Re: Problems running motors with sabertooth
Post by: jkerns on July 27, 2014, 07:27:39 AM
If you are running 35 amp motors through a 25 amp drive, it is likely that the driver is overheating and shutting down.

Too small wires will have a voltage drop across them and waste power and in the worst case melt the insulation, but they would not typically cause the symptoms you describe.
Title: Re: Problems running motors with sabertooth
Post by: Admin on July 27, 2014, 03:05:37 PM
jkerns is right, the motordriver is going into 'thermal shutdown'.

Ideally, you should use a motordriver of 35 amps.

Another option is to run your motors at a smaller voltage, or PWM to no more than perhaps 70% duty. While the driver might not overheat anymore, the motors would have very reduced torque/rpm.