There is a ground fault or a fault in the power
section.
During the ground fault test, a current flows
from the phase in which a valve has been
triggered, the overcurrent comparator has
responded, or a UCE monitoring has
responded in a phase in which a valve has
been triggered.
Read out fault value from r949. The digit of the
xth position indicates the valve where the fault
occurred at power-up.
X O O O x = 1 = V+ x = 2 = V- x = 3 =U+
X O O O x = 4 = U- x = 5 = W+ x = 6 = WCheck
the motor including the feeder cable for
short-circuit. If no ground fault is present,
check the power section for defective valves
(always conductive).
The digit of the xth position indicates the
phase in which I is 0 and therefore a valve
must be defective (always conductive).
O O O X 1 = Current in phase 1 (U)
2 = UCE in phase 2 (V)
3 = Current in phase 3 (W)
4 = Only overcurrent occurred
The speed of the motor shaft during the
ground-fault test should be less than 10 % of
the rated speed!
1) In phase V there is a ground fault or a
defective valve (always conductive) or the
"SAFE OFF" switch (X9/5-6) is open (only for
units with Order No. ...-11, ...-21, ...-31).