How Do You Test An Electric Motor Capacitor

Capacitors are metal tubes that store an electric charge usually found near a motor in the appliance.

How do you test an electric motor capacitor.

The cover must be removed to access the capacitor for inspection and testing. A bad motor capacitor may cause starting problems or could shut off the motor while running. A damaged or burnt out capacitor may hold only a fraction of the energy needed for the motor if its capacitance is low. Use needle nose pliers with an insulated handle to remove wires.

Check the start or run capacitor used for starting or running some motors if equipped. This article series gives electric motor start run capacitor and hard. Motor capacitors store electrical energy for the motor to use. Replace the capacitor if it fails the test again.

You can check to see whether a capacitor is good or bad using an ohm meter but first you have to remove the capacitor from the circuit and discharge it. Beyond just issues with the capacitor s multimeter readings it s possible to observe problems with the unit visually. To this test rotate the multimeter knob to the capacitance mode. Do not touch an electric motor capacitor nor any other.

To test an hvac run capacitor you ll need a multimeter. How to test an electric motor capacitor. Many household appliances have an electric motor start capacitor and when this wears out the motor doesn t have enough energy to cycle on. If the capacitor does not test as described above short out the capacitor leads one more time in case residual voltage is in the capacitor.

As a general rule of thumb electric motor start capacitors can be replaced with a micro farad or µf or mfd rating equal to or up to 20 higher µf than the original capacitor serving the motor on the replacement capacitor the voltage rating must be equal to or greater than the original. Use a screwdriver to open your machine and locate the capacitor. It should give you a digital reading ideally within 6 percent of the manufacturer specifications for the capacitor. You can do this test with a multimeter if you have a capacitance meter or you have a multimeter with a feature to test the capacitance.

Also this method is good to test the tiny capacitors as well. The higher the capacitance of the capacitor the more energy it can store. Retest the capacitor with the meter.