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Calculate Size of Capacitor Bank

Electrical Load of (1) 2 No’s of 120KW, 415V motor, 90% Efficiency, 0.8 P.F. (2) 2 No’s of 150KW, 415V motor, 90% Efficiency, 0.8 P.F. (3) 100KW, 415V Lighting Load. The targeted P.F. Of system is 0.98 Calculate Size of Discharge Resister for discharging of Capacitor Bank Discharge rate of capacitor is 55v in less than 1 minute. Also calculate reduction in KVAR Rating of capacitor if Capacitor bank is operated at frequency of 30Hz instead of 50Hz and if operating voltage is 390V instead of 415V Calculation:  For Connection (1): Total Load KW for Connection (1) =KW / Efficiency=(120×2) / 0.9=266.67KW  Total Load KVAR1= KW×([(√1-(Old P.F.)^2) / Old P.F.] - [(√1-(New P.F.)^2 / New P.F])   Total Load KVAR1=266.67×([(√1-(0.8)^2) / 0.8] - [(√1-(0.98)^2) / 0.98])    Total Load KVAR1=145.98 KVAR  OR  Total Load KVAR1= KW×(tanϕ1- tanϕ2) =266.67×(tan 36.87 - tan 11.48)                                                                     = 266.67×(0.75 - 0.203) 
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Sizing Of Diesel Generator

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Hardness and Hardness Testers

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High Speed Rails and How they Work?

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