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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

HOW TO CALCULATE THE UNCERTAINTY BUDGET OF pH METER.

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1. SOURCES OF UNCERTAINTY A. Repeatability (Type A) B. Buffers (Type B) C. Resolution of pH meter (Type B) D. Linearity (Type B) E. Temperature (Type B) 2. Quntification of Sources of Uncertainty A. Repeatability (Type A)                 Repeatability calculation (Type A Uncertainty)                             Formula / Expression of find the Repeatability (Standard uncertainty) Mean = AVERAGE(B4:B13) (X - Mean) = $B4-$C$4                   =UUT Value - Mean (X - Mean)^2 = ($D4)^2                             =( UUT Value - Mean)^2     Standard Deviation = STDEV(B4:B13)    Repeatability (Standard Uncertainty) =  F4/SQRT(10)                                                                                    =Standard Deviation / square root (number of Sample) B. Buffers: Following Buffers are used in Calibration of pH Meter: a) 4.01 with ± 0.02 uncertainty declared by manufacturer. b)7.00 with ± 0.01 uncertainty declared by manufacturer. c) 10.01 with ± 0.03 uncertainty declared by manu

pH Meter principle of Measurement and Source of Uncertainty.

pH  pH value is the logarithm of reciprocal of hydrogen iron activity in moles per liter. In water solution, variation in pH value from 7 are mainly due to hydrolysis of salts of strong bases and weak acids or vice ver se. Dissolved gases such as carbon dioxide, hydrogen sulphide and ammonia also affect pH value of water. The overall pH value range of natural water is generally between 6 and 8.In case of alkaline thermal spring water pH value may be more than 9 while for acidic thermal spring waters the pH may be 4 or less than 4.Intrustrial wastes may  be strongly acidic or basic and their effect on pH value of receiving water depends on the buffering capacity of water.The pH value obtained in the laboratory may not be the same as that  of water at the time of collection of samples due to loss or absorption of gases, reaction with sediments, hydrolysis and oxidation or reduction taking place within the sample. pH value should preferably be determined at the time of collection of sampl

METHORD OF CALCUATE THE SPEICIFIC GRAVITY OF A SPECIFIC GRAVITY CUP

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   First Calculate the Volume  Steps to Calculate the volume  1.Measure the Empty weight of the Specific gravity cup 2.Put Distilled water in the cup. 3.Measure the Weight of the cup after filled the distilled water. 4.Measure the temperature of the distilled water 5.Measure the Atmospheric pressure 6.Find the Z Factor from the Chart . 7.Convert the different in mass convert into volume by multiply by Z factor. Different in Mass =  Weight of the cup after filled the distilled water. - Empty weight of the Specific gravity cup      Second Find the Density of the Distilled water 1.Find the Mass of the Water 2.Find the Volume of distilled water. 3.Density = Mass / Volume Mass and density is getting from the Volume Section.     Specific Gravity = Calculated density / Density of distilled water at same temperature Below One Example to Show how to find the Specific Gravity Empty Weight of Specific Gravity Cup = 145.874 g Weight of cup after fill the Distilled water = 230.782 g Temperature of