Cause : Automatic field current reduction if EMF is too high in operation (active in operating states of – –, I, II)

This alarm is active only when parameter P272=1 and activated if the following equation applies to firing angle α (armature) before limitation (K101):

α > (αW (inverter stability limit acc. to P151) – 5 degrees) or ,

at a low (pulsating) current α > (165 degrees – 5 degrees)

AND armature current setpoint K0118 filtered with P190.F is > 1% of r072.002

The field is reduced simultaneously with A043, implemented through control of the armature firing angle to (αW (or 165 degrees)

- 5 degrees) using a P controller whose output reduces the EMF controller setpoint. For this reason, “Field weakening operation through internal EMF control” (PO81=1) must be parameterized.

When a change in torque direction is requested, both torque directions are inhibited until the calculated control angle (K101) is <165 degrees for the armature current requested in the new torque direction, i.e. until the field, and thus the EMF, have been reduced accordingly.
See also parameter P082.