Check:
ArmOvrCurLev (30.09) parameter settings of group 43 (current control: armature current controller tuning) current and torque limitation in group 20 all connections in the armature circuit, especially the incoming voltage for synchronizing. If the synchronizing voltage is not taken from the mains (e.g. via synchronizing transformer or 230 V / 115 V network) check that there is no phase shift between the same phases (use an oscilloscope).
- for faulty thyristors
- armature cabling
- in case of a rebuild kit proper connection of firing pulses and CT’s
-if TypeCode (97.01) = None and S ConvScaleCur (97.02) is set properly