3.75MW, 11kV Induction motor is connected in 33kV system through a Unit Trafo (33/11kV). There is a capacitor across motor terminals and compensates about 90% of the motor magnetising current. The feeder is tripping on Differential protection. The differential protection covers motor and transformer in its zone but excludes the capacitor. The differential protection is bias type (KBCH130 of AREVA). Apparently, there is no problem with either the motor or transformer.
Red Flag Submitted
Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action.
Reply To This Thread
Posting in the Eng-Tips forums is a member-only feature.