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How do we derate S801+ and S811+ Soft Starters for temperature?

S801+ and S811+ Soft Starters have a maximum operating temperature of 50 degrees Celsius. Since the electronic components are the same for each frame, the 50 C environment rating takes precedence. Higher ambient temperatures above 50 C can have a drying effect on the electronic components and shorten the life of the device. The EMM18 fan kit is encouraged, as it will drop the temperature around the printed circuit board by about 5 to 8 degrees Celsius.

When looking at pole temperature, the focus should be on derating the unit so that the expected current does not exceed the maximum. For example, the T30 frame values are based on a 304 Amp rating, so that the maximum allowable temperature will not be exceeded. By moving to a T36 frame, a greater level of current (heat) during ramp time can be tolerated before reaching the maximum allowable temperature.


For more information, see our S811+/S801+ Product Overview