IEC motor application in NEMA land
IEC motor application in NEMA land
(OP)
We plan to use VFD with AC motor built in Europe, and carrying reference to Standard IEC 60034 on the motor name plate. Are there any data/materials which could help to prove to end user that there is a close correlation between IEC 60034 and NEMA MG-1, Part 31 with regards to inverter duty motor design? I am thinking of white paper with comparison of both standards.





RE: IEC motor application in NEMA land
5.3 Additional motor-losses when operated on a frequency converter.
5.9 Matching motors and variable frequency converters
5.13 Variable frequency converter efficiency
5.14 Frequency converter power factor
and part 7 Applications:
7.2 Energy savings by speed control (variable speed drives, VSD)
RE: IEC motor application in NEMA land
Sounds like your end-user expects you to actually comply with his specification?
David Castor
www.cvoes.com
RE: IEC motor application in NEMA land
I'm not aware of any documents that refer NEMA to IEC of vice-versa when it comes to inverter ratings. There are numerous papers out there specific to each one so it might pay to look at motor manufacturers who build for both markets. I cannot imagine they would use techniques too differently for both.
However, one of the key variables (no pun intended) will be the type of VFD you use and how you are using it.
The switching frequency, the distance you are away from the motor, the voltage you are connected to, methodology of switching.
Not all VFD's are the same.
"Inverter rated motor" is a rather generalist statement and cannot be used in isolation of the VFD, how it is used and where.
A problem a lot of people fall into is not always long motor cable length but very short cable lengths too. The dv/dt level will be very high due to the high rise time.
The attached document from WEG is an interesting one but fails to highlight the impact of short distance between the VFD and motor.
http:/
RE: IEC motor application in NEMA land