Newbie with 24v Controller Question

Hello, I am using a 24v wheel chair motor and transaxle to build a motorized cart. I have built the frame with 80/20 and using 15" OD turf tires (small lawn tractor tires) I am running with two 12v batteries wired to 24v. The motor is rated at 24v 800 watt brushed motor. I have used a 40amp 1200 watt controller but when testing it I took it slightly off road with a 50lb weight on it, the controller over heated and got smoked. It works fine on pavement or dirt trail.
Any help on choosing a controller that will handle a heavier load and maybe a 10-15% grade would be great or what am I missing? Thank you!

Hello @ktech and welcome to the RobotShop forum,

When choosing a motor controller you have to keep the nominal/rated voltage and current values in mind but you also need to know what happens if the motors stall.

Rated current is the maximum recommended current that should be allowed to continuously be applied to the motor - although, in some rare cases, the rated current is given for when the motor is most efficient.

Stall current is the highest current that the motor can draw (when it is running under maximum torque load). You should make sure that your motor driver is capable of handling this current if possible, otherwise you risk burning out your electronics if the motor sticks and draws the stall current.

This is what happened to your motor controller, the motors stalled and demanded more current than what your controller could handle. This is why choosing a motor controller with built-in over current and thermal protection is a very good choice.

Since you mentioned 40A weren’t enough for your motors this could be a good choice:

60A continuous and 120A peak with overcurrent and thermal protection. But you can also check the 30A+ DC Controllers section for more options.

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