Machine Parts

It is used for determining the interrupting capacity of a circuit breaker or fuse employed to protect the primary of a transformer. Example : Determine a minimum circuit breaker trip rating and interrupting capacity for a 10 KVA single phase transformer with 4% impedance, to be operated from a 480 volt 60 Hz source. Calculate as follows: Normal Full Load Current = Nameplate Volt Amps 10,000 VA __________________ = __________ =                             Line Volts 480 V                                                           20.8 A...

Impedance is the current limiting characteristic of a transformer and is expressed in percentage.