IEC 60034-28:2012 applies to three-phase low-voltage cage induction motors of frame numbers 56 to 400 as specified in IEC 60072-1. This standard establishes procedures to obtain values for elements of single phase equivalent circuit diagrams from tests and defines standard elements of these diagrams. This edition includes the following significant technical changes with respect to the previous edition:
- the formulae are now all given for equivalent star-connection equivalent circuit diagrams;
- procedures for the determination of equivalent circuit parameters from a load curve test as an alternative to the reverse rotation and locked rotor tests have been added.