First of all, please accept my thanks for your great and valuable assistance.
To set function ANSI 49 for protection of electromotors, motor thermal time constant is needed which should be specified by motor manufacturer. Very often this value is not available, what is typical value for example 500KW 6.6 KV and 800 KW motors? what about larger motors?
I would highly appreciate if you share your knowledge and experience on this subject.