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SERVICE FACTOR OF MOTOR

Service factor is the factor that, when applied to rated output, represents the allowable load that can be applied to motor continuously, under specified operating conditions. Note that this refers to continuous overload conditions, i.e., a power reserve that gives the motor a better capacity to withstand adverse operating conditions. Service factor should not be confused with momentary overload capacity during few minutes. A service factor = 1.0 means that the motor has not been designed for continuous operation above its rated output. However, this does not change its capacity to withstand instantaneous overloads. NBR 17094 specifies the most common Service Factors per motor output.

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