The U.S. motor industry has worked on a standardized basis for more than three-quarters of a century. The standardization agency National Electrical Manufacturers Association (NEMA) was established in 1926 to promote the standardization of electrical apparatus and supplies. As a result of this group's efforts, you can expect motors from different manufacturers to meet or exceed minimum performance
Discuss this Article 2
Hi i have a question i was looking at a 3 phase star/delta set up and notices the overload was lower than expected it was a 37kw motor which is 66 amps to my calculations but overload was 38 i think roughly. I looked on the motor and found at 50hz 660v at star gave the same amps as what the overload was set at. do u understand what im on about as we only work 3 phase at 415. i would be really greatfull if u could help me
thank you
Dear as you are working on 415V so definitely the amperes which you have calculated are exact. On 415V just the thing you have to do is that increase the adjustments of overload at almost 70amp to be on safe side. As you will increase in volts the value of current will decrease so at 660V the adjustment of overload is right which is 38Amps.






