Assume a bank of heating strips is rated at 20 K W and is connected to 240 volts. The heat strips operate for 4 hours at a time and are located in an area with an ambient temperature of 96 degrees F. The termination temperature rating of the heat disconnect lugs is unknown. Three (3) Copper conductors installed in a conduit with type THWN-2 insulation are to be used to connect the heaters. What size conductors should be used?

Assume a bank of heating strips is rated at 20 K W and is connected to 240 volts. The heat strips operate for 4 hours at a time and are located in an area with an ambient temperature of 96 degrees F. The termination temperature rating of the heat disconnect lugs is unknown. Three (3) Copper conductors installed in a conduit with type THWN-2 insulation are to be used to connect the heaters. What size conductors should be used?

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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