Heat Exchanger Selection Example

A NEMA 12 Hubbell Wiegmann N12302412 enclosure (30″ high x 24″ wide x 12″ deep) contains a GS3-4010 AC drive 10 HP 460 volt) that has a maximum allowable operating temperature of 104°F and is located in a warehouse that has a maximum outside ambient air temperature of 90°F.

Power to be dissipated is stated in the specifications of the GS3-4010 and is found to be 345 watts.

Internal heat load:

Internal Heat Load = 345 Watts

Delta T:
∆T (°F) 104°F – 90°F = 14°F

Heat load transfer:

Surface Area (ft.²) = 2 [(30 x 24) + (30 x 12) + (24 x 12)] / 144 sq. inches = 19 ft.²

Heat Load Transfer = 0.22 x 19 ft.² = 4.2 Watts/°F

Cooling capacity:

Cooling Capacity = 345 Watts/14°F – 4.2 Watts/°F = 20.4 Watts/°F

In this example, you are able to determine that a Stratus heat exchanger, with a capacity of at least 20.4 Watts/°F is needed, such as a TE30-030-17-04.

*This selection procedure applies to metal and non-metal, uninsulated, sealed enclosures in indoor locations. This selection procedure gives the minimum required size; be careful not to undersize when purchasing.