How to Test a DC Motor

DC Motor: The motor you want to test.

Power Supply: A DC power source to provide voltage to the motor. This can be a battery, a power supply unit, or even a DC power adapter.

Wires: Electrical wires with alligator clips or connectors.

Multimeter: A multimeter set to measure voltage, current, and resistance.

Bench or Work Area: A safe and stable surface to work on.

Safety Precautions: Ensure that the power source and motor are disconnected before starting the test. Wear appropriate safety gear, including safety goggles and gloves if necessary.

Identify the Motor Terminals: DC motors typically have two terminals, one for the positive (red) and one for the negative (black). The terminal markings may vary from motor to motor, but they are often labeled as "+" and "-" or "A" and "B."

Connect the Power Supply: Use electrical wires to connect the positive (red) terminal of your power supply to one of the motor terminals and the negative (black) terminal of the power supply to the other motor terminal. Ensure proper polarity, as reversing it may cause the motor to spin in the opposite direction.

Inspect the Motor: Look at the motor as you apply power. It should start to rotate. If it doesn't, check the connections, and make sure the power supply is functioning correctly.

Measure Voltage: Using the multimeter, set it to measure DC voltage. Place the red probe on the positive terminal of the power supply and the black probe on the negative terminal. The voltage should match the rating of your power supply (e.g., 12V, 24V).

Measure Current: Set the multimeter to measure DC current. Disconnect one of the wires connected to the motor terminals and insert the multimeter in series. Connect the red multimeter probe to the positive terminal of the motor, and the black probe to the wire that was disconnected. Activate the motor and observe the current draw. The current should be within the motor's specified operating range.

Check Resistance: To check the resistance of the motor, set the multimeter to measure resistance (ohms). Disconnect the motor from the power supply and measure the resistance between the two motor terminals. The resistance should not be too low (a few ohms) or too high (infinite resistance), as this could indicate a problem with the motor windings.

Listen and Observe: While the motor is running, listen for any unusual sounds, and observe its performance. Vibrations, unusual noises, or erratic behavior can be signs of motor issues.

Reversing Direction: If your motor has reversible polarity (most DC motors do), swap the connections to reverse the motor's direction.

Disconnect Safely: After testing, disconnect the power supply and any electrical connections safely.

Jump Motor Leads: Disconnect the motor from the board and any other sources. Use a conductive piece of metal (like a staple) and jump the two motor wires together. No try to move the treadmill belt and it should be very difficult to move. If you remove the jumper, then the belt should move much easier. If this is true in your situation, then it is likely the motor is good.