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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CALIBRATION PROCEDURE OF TEMPERATURE CHART RECORDER

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    1.  Apply a temperature equal to 50% of the total temperature range.
    2. Adjust the drive arm and the driven arm until they form an approximate 90°angle with the intermediate arm.
    3. Reduce the temperature to zero or the starting point of the temperature range.Fine tune the zero adjustment with the zero adjustment screw.
    4. Apply 100% temperature and set the pen to full scale by turning the adjusting screw.
    5. Reduce the temperature to zero or the starting point of  the temperature range and check the zero reading. if the reading is correct ,proceed to step 7.
    6. If zero adjustment is required, repeat step 3 through 5 until desired accuracy is achieved.
    7. Apply 50% temperature and observe the pen indication.
                    a. If the pen indicates high or low ,adjust the drive link to make a correction                         approximately 40 times the error -  in the direction of the error.
                    b. Reset the pen to the 50 % line by slipping the pen at the range arm pivot                             point.

       
       8.  Reduce the temperature to zero or the starting point of the temperature range and              reset the zero point 
                   a.    If the zero offset is minor,reset the zero point with zero adjust screw.
                   b.    if the zero offset is major, reset the zero point by loosening the bourdon mounting screws and rotating the connecting linkage to approximately zero. Fine - tune the zero adjustment with the zero adjust screw.
        10. Repeat step 3 through until desired accuracy is maintained.

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