NEMA motor lead nomenclature

[thewirenut91]

Hey all,
Does anyone have a great resource on the logic of NEMA motor lead naming or designation? More specifically, why some six lead, three phase motors are labeled (1,2,3--4,5,6,), and some are (1,2,3--7,8,9)? For instance, does a 6 lead PWS motor have differently numbered leads than a 6 lead dual voltage motor? know Google is my friend, but our relationship is under strain over this issue.
Maybe motor lead naming is more arbitrary and manufacturer specific? It really becomes an issue when refurbished motors lose their labels and you have to start ringing them out.

 

[infinity]

More specifically, why some six lead, three phase motors are labeled (1,2,3--4,5,6,), and some are (1,2,3--7,8,9)?

In general I always through that motor leads were numbered according to a standard that why we learned how to connect them for example in either a Wye or Delta configuration. Could the six lead 1,2,3-7,8,9 have 4,5,6 internally connected because a low voltage Wye configuration would have you tie those three together anyway? Maybe a motor guru will chime in.

 

[FionaZuppa]

see https://bradleysmotors.com/PDFs/Terminal_Markings_and_Motor_Connections.pdf

 

[thewirenut91]

thanks!