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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BRINELL HARDNESS ASTM E10 SYMBOL AND DESIGNATIONS

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Symbol

Designation

Unit

D

Diameter of the ball

mm

F

Test Force

N

Fkgf

Test Force

kgf

d

Mean Diameter of the indentation

mm

h

Depth of the indentation

mm

Force Diameter Ratio

 \[\frac{Fkgf}{D^2}\]

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HBW

Brinell Hardness

Test Force / Surface area of Indentation

\[\frac{Fkgf}{πD(D-\sqrt{(D^2-d^2 )}}\]


 

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