Cause : Phase failure in armature supply. The supply voltage RMS value, calculated from the area of each supply half-wave (rectified average value * peak factor), must be greater than the response value for phase failure monitoring.

The distance between two identical supply zero passages of a phase must not exceed 450 degrees. If one of these two conditions remains unfulfilled for longer than the “restart time” set in P086, a fault message is activated. After switch-on, the converter waits in operating states o4 and o5 together for a period not exceeding the setting in P089 for voltage to appear at the power terminals (and for field current) before activating the fault message.

Possible fault causes:
♦ Parameter P353 is incorrectly set
♦ Armature phase has failed
♦ Line contactor opened in operation
♦ Fuse has blown on three-phase side in armature circuit
♦ Fuse has blown in power section
♦ Interruption in a thyristor firing pulse cable (auxiliary cathodes at connectors X12, X14, X16 are voltage carriers).

1 Voltage failure has occurred in armature supply (1U1, 1V1, 1W1) (when P086=0)
2 Delay time set in parameter P089 has expired in operating state o4
3 Fuse has blown in power section
4 Voltage failure has lasted longer than period set in P086 (if this is >0)
6 The "Main contactor checkback" (control word 2 bit 31) [see also P691] did not switch to "1" before the time set in P095 ran out, or switched back to "0" during operation [V1.8 and later].