KVAR RATING CALCULATOR,CAPACITOR BANK SIZE CALCULATION

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 Determination of Required Capacitor Rating by measurement


3 Methods are used.
1. Measurement with current and power factor
2.Measurement with recording of Active and Reactive power.
3.Measurement by Reading Meters.

1. Measurement with Current and power factor

The active power P is calculate from the measured voltage V ,apparent current Is and Power Factor

P=√3*Voltage*apparent Current*cosψ *10^-3

If the desired power factor cosψ has been specified, the capacitor power rating can be calculate from the following formula:

Qc = P. (tan ψactual - tanψ desired)

Let's See the Example
Measured Apparent Current Is : 248 Amps
Power Factor cos ψ1 = 0.86
Desired Cos ψ2 = 0.92



Voltage V :397 V
p=√3 * 397 * 248 * 0.86 * 103
P = 146.6 KW



Qc= P. (tanψ actual - tanψ desired)

= 146.6(0.59 - 0.42)

= 24.9 KVAR








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