A 30- hp squirrel cage induction motor is connected to a 240-volt three phase feeder. The motor is to be replaced with a 50-hp squirrel cage induction motor connected to 480 volts. The motor has a nema code b, a full load current of 49.8 amps, and an sf of 1.10. the present conductors are 3 awg copper with thwn insulation. Are these conductors sufficient to connect to the 50-hp motor or will they have to be replaced

A 30- hp squirrel cage induction motor is connected to a 240-volt three phase feeder. The motor is to be replaced with a 50-hp squirrel cage induction motor connected to 480 volts. The motor has a nema code b, a full load current of 49.8 amps, and an sf of 1.10. the present conductors are 3 awg copper with thwn insulation. Are these conductors sufficient to connect to the 50-hp motor or will they have to be replaced

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter10: Using Wire Tables And Determining Conductor Sizes

Section: Chapter Questions

Problem 6PP: 6. A 50-hp DC motor is connected to 250 volts. The motor does not contain a NEMA code. The motor is...

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