Question 11.7: Assume that a bank of heating resistors is rated at 28 kW an...

Delmar’s Standard Textbook of Electricity

Assume that a bank of heating resistors is rated at 28 kW and is connected to 240 V. The resistors operate for more than three hours at a time and are located in an area with an ambient temperature of 86ºF. Aluminum conductors with Type THWN-2 insulation are to be used to connect the heaters. What size conductors should be used?

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