Service factor (a NEMA term) represents how much over the “nameplate rating” an AC motor can by driven without overheating. The OM catalog states rated torque which represents 100% of the load that should be applied to the motor, at the specified ambient temperature range. We don’t recommend any value over the rated torque, and have not tested for loads which will result in overheating. Therefore, our service factor is unity, or 1.0.
If the overloading is a result of the acceleration. and deceleration of the load to the motor, then the sizing of the motor needs to be considered. The starting torque would have to be greater than the total of acceleration torque and constant torque, multiplied by some safety factor.
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