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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ACCURACY OR MAXIMUM PERMISSIBLE ERROR OF STEEL SCALE AS PER BS :4372

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 Graduation lines shall be accurate to within the tolerances specified in table below. These tolerances apply to the distances between the centre  lines of the graduation lines.

Rule Length

Departure from nominal

Up to and inc. 300 mm

Over  300 mm up to and inc. 500 mm

Over  500 mm up to and inc. 1 m

Distance between any two graduation lines on a single scale

0.1 mm

0.2 mm

0.25 mm

Distance between any two adjacent graduation lines.

0.05 mm

0.05 mm

0.05 mm

Position of the 10 mm graduation line from its flat end datum

0.08 mm

0.08 mm

0.08 mm


















                        Accuracy of Graduation

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