Currently I am working in Germany assisting OEMs to built their machinery for the use in the US.
In a lot of cases the question which voltage is the nominal voltage and why do Motors have a different voltage rating as Circuit Breakers leads to a almost never ending discussion.
My opinion, e.g. 480V is the nominal voltage of the power transformer system. 460V on the motors specifies, that this motor can be used with 100% load at 480V minus 4% defined voltage drop, without the risk of overtemperature.
But the question than will be - what happens if the motor is used directly at the transformer terminals including the plus tolerance - this would be 480+10% = 528V. Will the motor than have troubles, like isolation, overvoltage, ...?
How does the UL standard for motors address this?
Many thanks for your reply
Best regards
Gustav
In a lot of cases the question which voltage is the nominal voltage and why do Motors have a different voltage rating as Circuit Breakers leads to a almost never ending discussion.
My opinion, e.g. 480V is the nominal voltage of the power transformer system. 460V on the motors specifies, that this motor can be used with 100% load at 480V minus 4% defined voltage drop, without the risk of overtemperature.
But the question than will be - what happens if the motor is used directly at the transformer terminals including the plus tolerance - this would be 480+10% = 528V. Will the motor than have troubles, like isolation, overvoltage, ...?
How does the UL standard for motors address this?
Many thanks for your reply
Best regards
Gustav