If a motor has a run capacitor, does it also have a start capacitor?

Question

What does 370 volt 30 mic mean? Is that how much it outputs? Can I use the 370 v 30 mic to replace a capacitor that was 240 volt 30 mic?

Answer 1

The purpose of motor capacitor is to provide a single phase motor with phase displacement so that it can start as soon as you turn the switch on. Three phase motors are self starting and thus do not need capacitors to run. Some types of motors have dual, and others single capacitors. Some motors are called, "capacitor start, induction run" - meaning that the capacitor is automatically disconnected by a centrifugal switch shortly after the motor gets up to speed. Other motors are called, "capacitor start, capacitor run" meaning that the capacitor stays in the circuit after the motor gets up to speed. Assuming that you were referring to residentially use motors such as an airconditoning, you maybe referring to the 220-240 volt single phase which is generally used in household electric clothes drier, forced air ovens and centralized air conditioning. The utility circuit (lights, coffee maker, etc) used 120VAC. The "mic" you were referring to is actually "mfd" (microfarads). That's how capacitors are rated. So 370 volts, 30 mfd sounds somewhat odd. You perhaps meant 240 volts, 30 mfds. Hope this helps.

Answer 2

Most motors that are capacitor run are also capacitor start. I have not heard of mic of capacitors, you sure it is not mfd? If it is mic would be grateful if you could give me full form of it. You can use a 370 volts in place of 240 it is normally not done as the price goes up with the volts. You cant do it the other way round ie 240 in place of 370 as the capacitor would blow up.

Answer 3

Could have one or the other or both. Some motors have start capacitors for extra torque when starting some have them for running and some have start and run capacitors. As far as the info goes don't replace anything that doesn't match perfectly. Without being there to see it I cant make judgment. 30 Mic could possibly mean maximum inrush current. Not sure.voltage is what the motor is rated at.