I have a small dc motor that draws 1.5 - 2 amps under load with 12V.
I have it set up to lift a weight when turned on. The load torque is close to 75% of stall.
When connected directly to a battery is works fine.
I'm trying to run the motor with a IRF 540 rated at 28A continuous and 110A pulsed.
I have the fairly large heat sink on the mosfet and a flyback diode.
When I apply 5v to the gate the mosfet will handle smalled loads but the motor.
Is it possible the rush current is exceeding 28A?
duinoMike:
I'm trying to run the motor with a IRF 540 rated at 28A continuous and 110A pulsed.
The IRF540 is not a logic level mosfet, and needs 10volt at the gate to fully turn on.
With the 5volt (assuming) from the Arduino, it only turns partially on, resulting in not enough current to the motor and the fet getting hot.
Leo..
Swap the MOSFET for an IRL540 (or one of many other logic level MOSFETs) and it will work much better.
Steve
Thank you!
Glad to know there is a mosfet solutuon. Thought maybe I'd lave to go to a heavy duty relay.
Whatever solution add a free-wheel diode across the motor.