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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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UNCERTAINTY OF MEASUREMENT OF ANALOGUE PRESSURE GAUGE

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  SOURCE OF UNCERTAINTY OF PRESSURE GAUGE Repeatability of the unit under test. Resolution of UUT Expanded Uncertainty of Master Instrument Hysteresis Error Drift of the Master Instrument\ Uncorrected Error of Master Instrument   Calibration Result    1.0  Repeatability of the instrument (U 1 ) Uncertainty from the repeatability  = 0.05774 bar 2.0  Resolution of UUT (U 2 )           Resolution of UUT  = 1 bar      Uncertainty from the resolution of the UUT =              = (1/5)/sqrt (3)                                           =0.1154700 bar                                 3.0  Uncertainty of Master Instrument (U 3 ) Expanded Uncertainty of Master Instrument  = ...
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Estimation of Uncertainty in Hardness Measurement & Maximum Permissible Error of Brinell Hardness Testing Machine As Per ISO 6506-2 & ASTM E10-15

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Source of Uncertainty of Hardness Measurement Certified Value of CRM Determine the User Machine Repeatability Assessment according EN ISO 6506 Uncertainty from the Measured Material. Resolution of the Indentation diameter measuring device.                            1. Certified Value of CRM       Xcrm = 222 HBW 10/3000    Ucrm    = 土 1.4 HBW  (2σ Uncertainty) 2 . Determine the User Machine Repeatability       H₁ = 221     H₂ = 220      H₃ = 220      H₄ = 221      H₅ = 220     Mean = 220  HBW                      b )  Repeatability of  Hardness Measurement                      H₅ = 220              ...
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HOW TO FIND THE RELATIVE REPATABILITY & RELATIVE REVERSABILITY OF LOAD CELL

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Load Cell A load cell is a transducer that is used to convert a force into electrical signal. A load cell usually consists of four strain gauges in a Wheatstone’s’ bridge configuration on an elastic element. Relative Repeatability=( ( F max -F min )/ F avg )*100 Relative reversibility =((F-F')/F(avg))*100 Where F:applied incremental force, F': applied decremental force,  Arithmetic Mean of indicated force                                                             Applied force kN Indicated Deflection Test 1 Test 2 Test 3 0.4 0.41 0.41      0.41 0.8 0.82 0.82 0.82 1.6 1.62 ...
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