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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ACCURAY OF BRINELL HARDNESS INDENTATION MEASURING DEVICE AS PER ASTM STANDARD

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BRINEL HARDNESS BALL DIAMETER MEASUREMENT DEVICE & ACCURACY OR PERMISSIBLE ERROR OR ACCEPTANCE CRITERIA
 

Ball diameter measurement device is the integral part or standalone part of the Hardness machine.

The measurement devices are classified into two types.

Type A Device & Type B device

Type A

Type B

Includes microscope having movable measuring line.

Use some type of indicator or computerised measuring system or image analysis system.

Hand held microscope with fixed measuring lines

 

Usually used (20X or 40X)

 

 Resolution and Graduation Spacing of Indentation Measuring Device

Ball Diameter (mm)

Type A

Type B

Minimum indicator Resolution (mm)

Maximum Graduation Spacing (mm)

10

0.0100

0.100

5

0.0050

0.050

2.5

0.0025

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1

0.001

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