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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

ASTM E10 ACCURACY,MAXIMUM PERMISSIBLE ERROR,ACCEPTANCE CRITERIA & MAXIMUM PERMISSIBLE REPEATABILITY OF HARDNESS TESTING MACHINE

  Repeatability and Error of the Testing Machine

ACCURACY ,ACCEPTANCE CRITERIA ,TOLERANCE OF MEASURING TAPE

  For Class I Tape Accuracy ±(0.2+0.1*L) mm For Class II Tape Accuracy ±(0.25+0.15*L) mm L is a value of length measured in metres, rounded up to an integer and expressed without units. For Class 2 tape measures, the result of above calculation shall be rounded up to one decimal place.

ASTM E10-15 BRINELL HARDNES NUMBER IS CALCULATED AS

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 BRINELL HARDNESS NUMBER (HBW) HBW =   2xF kgf   / π D( D- √ D 2 -d 2 ) F kgf = Test Force in kgf D      = Diameter of the indenter ball in mm d      = Measured mean diameter of the indentation in mm Ball Diameter = D=10 mm Test Force = Kgf = 3000 Brinell Hardness Number Equation & Solution

Calculate the specific weight, mass density, specific gravity and specific volume

 Calculate the specific weight, mass density, specific gravity and specific volume of oil having a volume of 4.5m³ and weight of 40kN? Data is given in the Question. Volume of Oil =4.5m³  weight of oil =40kN =40X10³ N 1. Specific Weight: w=weight of oil/Volume of oil    =40X10³ N/4.5    = 8.889X10³ N/m³  2. Mass Density of oil ρ=Specific weight of oil / Acceleration due to gravity  =w/g = 8.889X10³ N/m³ / 9.81 = 906.1 kg/m³  3.Specific gravity of Oil S=Specific weight of Oil / Specific weight of water   = 8.889X10³ N/m³ / 9.81  = 0.906 4. Specific Volume of Oil   V=1/ ρ     =1/ 906.1 kg/m³     =1.1x10^-3    m³/kg   

S.I UNITS (INTERNATIONAL SYSTEMS OF UNITS)

  Quantity Units Symbol Length Metre m Mass Kilogram Kg Time Second S Electric Current Ampere A Thermodynamic Temperature Degree Kelvin °K Luminous Intensity Candala Cd

PROPERTIES OF FLUID

 Mass Density ( ρ) Specific Weight (w) Specific Volume (v) Specific Gravity (S) Temperature Viscosity Bulk Modulus (K) Compressibility Vapour Pressure Gas Laws Capillarity Surface Tension