Capacitor KVAR Rating

In the power system, the capacitors are used for supplying the reactive power which is consumed by the reactive loads like motors. The unit of reactive power is kVAR.

If you know the capacitance value, and voltage and frequency of the system, here is how to find the kVAR:

(1) Find the capacitive reactance, Xc:

Xc = 1/(2 x PI x f x C) ohm

Where C = capacitance in micro-farads, f = frequency and PI = 3.14

(2) Find the kVAR rating of the capacitors:

kVAR = (Vn)²/(Xc x 1000)

Where, Vn = Voltage applied to the capacitor terminals

For the 3 phase system, the total kVAR rating is 3 times of this kVAR value.

The previous thread http://cr4.globalspec.com/thread/54230 also will help.

- MS