What capacitor do I need for my motor?
| Small Motor Capacitor “Ballpark” Sizes Based on Motor Horsepower | ||
|---|---|---|
| Motor Horsepower 2 | Start Capacitor µF / Voltage | Run Capacitor |
| 1 Hp or 0.75 KW, 120-150 VAC | 500-580 µF | 10-15 µF 370VAC |
| 2 Hp or 1.5 KW, 200-250VAC | 500-580 µF | 10-15 µF 370VAC |
| 3 Hp or 2.25 KW, 200-250VAC | 500-580 µF | 20-25 µF 370VAC |
Why does an electric motor need a capacitor?
Some single-phase AC electric motors require a “run capacitor” to energize the second-phase winding (auxiliary coil) to create a rotating magnetic field while the motor is running. This hesitation can cause the motor to become noisy, increase energy consumption, cause performance to drop and the motor to overheat.
What is the VC of a running capacitor?
The motor working voltage ( Vc ) is about 1,5-2 times the mains supply and decrease with the increase of the load.With capacitive reactive power of about 75% of the nominal power of the motor, the comparison of power is slightly lower than that of a three-phase motor of equal size. For running capacitor are rated in a range of 3-70 microfarad.
Can a capacitor be used as a motor?
When install a motor using capacitor for starting or running methods,we must sizing the rated of capacitor suitable with motor to get correct starting torque and avoid winding from overheating and can cause a damage.
What is the capacitance of an AC motor?
These capacitors usually have capacitance values of over 70 µF. They come in various voltage ratings, depending on the application they were intended for. Some single phase AC motor designs use motor run capacitors, which are left connected to the auxiliary coil even after the start capacitor is disconnected by the centrifugal switch.
What is the voltage of a start capacitor?
Starting capacitor (electrolytic) The capacitance has to be such as to provide a reactive power about double of the nominal power of the motor with a Vc ( motor working voltage ).Start capacitors normally ratings of 70 micro farad or higher.It also have three voltage classifications: 125V, 250V, and 330V.