440 volt machine on 480 volt system ?

[don_resqcapt19]

That is an issue with the code language. The equipment voltage for a motor is always less than the nominal system voltage. The nominal system voltage is 480 now, and the motor voltage is almost always 460.

110.4 Voltages. Throughout this Code, the voltage considered shall be that at which the circuit operates. The voltage rating of electrical equipment shall not be less than the nominal voltage of a circuit to which it is connected.

In this case, I expect the motor is fairly old, from when the nominal system voltage was 460 and the equipment voltages were 440.