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In: Mechanical Engineering

A three phase 30 hp 460 volt 60 hz, 1770 rpm design B induction motor with...

A three phase 30 hp 460 volt 60 hz, 1770 rpm design B induction motor with class F insulation and service factor of 1.0 is operating at rated shaft load in a 40 degree C environment and has an expected 20 yr life. A maintenance check shows line to line voltages to be 449.2 V, 431.3 V and 462.4 volts. The percent unbalanced voltage for this motor is:

the expected temperature rise equals?

The expected insulation life equals?

the rerating in horsepower equals?

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