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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EXPANDED FORM OF BRINELL HARDNESS SCALE - HOW TO READ THE BRINELL HARDNESS SCALE

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BRINELL HARDESS SCALE REPRASENTATION

WW HBW XX/YY/ZZ

350 HBW 5/750/10

 

WW : Brinell Hardness Numbers shall be followed by the symbol HBW ,

XX:.Diameter of the ball ,mm

YY :Test force ,kgf

ZZ:Applied Force dwell time,s

 

READING METHOD OF BRINELL HARDNESS SCALE 

Brinell Hardness Scale

Expanded From of Hardness Scale

350 HBW 5/750

Brinell Hardness of 350 determined with a ball of 5mm diameter and with a test force of  750 kgf applied for 10s to 15 s

600 HBW 1/30/20

Brinell Hardness of 600 determined with a ball of 1 mm and with a test force of 30 kgf of  20s

 

Brinell Hardness Number is calculated

Brinell Hardness Number

A number, which is proportional to the quotient obtained by dividing the test force by the curved surface of the indentation which is assumed to be spherical and of the diameter of the ball

How to find the Hardness Number (HBW)

Brinell Hardness Number is Calculated


Brinell Hardness Scale

A designation that identifies the specific combination of ball diameter and applied force used to perform the Brinell hardness test

 

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