Electrical Thumb Rules

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1.   Full load current of any motor based on HP,
                                  Full load current = 1.5 x H.P               
                   For 5 hp motor full load current = 1.5 x 5
                                                             = 7.5 A
2.   Capacitor Bank for any Industry = 1/3 x Total H.P of     
   Company
      Ex- For 15000hp capacity industry capacitor bank
= 1/3 x 15000
                                        Q = 5000 KVAR

3.   Number of Suspension insulators for various voltages.
          No of insulators= (Nominal phase   Voltage) / 11
                    Ex- For 66 KV Transmission line
                 No of insulators = (66/1.732)/11
                                            = 4 +1 (safety)
                                            = 5





                                               

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