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Motor Capacitors


What are Motor Capacitors and Why Do You Need One

A capacitor is a device that is used to store electrical energy temporarily. A motor capacitor specifically is an electrical device that stores energy and then transfers it to one or more windings of a motor in order to create a magnetic field. This field then keeps the rotor inside the motor spinning in perfect balance. Commonly used in HVAC applications, there are two main types of capacitor, run capacitors and start capacitors, both of which will be examined below.

Start Capacitors

The purpose of a start capacitor is to allow a motor to be started. It supplies energy into the motor at a rapid rate on start up, giving it enough energy to power it on. At that point, the start capacitor’s job is done and a centrifugal switch isolates the start capacitor.

Run Capacitors

Slightly less efficient and possessing a much shorter lifespan than start capacitors, run capacitors are designed to provide a magnetic field to support the spinning rotor throughout the time that the motor is running.

The Importance of Motor Capacitors and Where to Find Replacements

As you can see, motor capacitors have a very important job when it comes to the operation of a rotor. If a start capacitor fails, you won’t be able to even get your motor running, while if a run capacitor isn’t operating properly, the motor will overheat and ultimately fail. If you have either of these motor capacitors and they stop working, you can buy a new one from Edington Agencies, a locally owned company that specialises in electric motors.