Rockwell Automation Publication 20P-TG003B-EN-P - September 2021
141
Flow Charts
Appendix C
Field Current Loss Failure
The charts below presents the steps in flow chart form for troubleshooting a Field
Current Loss fault (F6).
No Field Current
Measure the
voltage at
terminals U1, V1.
Is the correct
voltage present at
U1, V1?
Verify the wiring and
power source to U1,
V1 and correct any
problems.
No
Remove AC power
and remove and test
the fuses (FU1, FV1)
at the bottom of the
drive.
Are the fuses
blown?
Test the resistance of
the motor field wiring
and motor field for
short circuits.
No
Yes
Yes
Are terminals
short circuited?
Are the fuses
blown?
Yes
Measure the gate
signals at pins XR-1
and XR-2 on the
cable.
Are the signals
present and
correct?
Replace the field
board.
No
Yes
Replace the
control board.
Disconnect cable from XR on the
control board and measure the U1-
V1 voltage synchronization signal
at pin 11 on the cable. This signal
should be a square wave signal
with a 90° lag phase displacement
compared to the AC voltage signal.
Repair short circuits.
Yes
Check the field SCR/
dual diode module for
a short circuit
condition.
No
Does a short
circuit condition
exist?
No
Yes
Replace the SCR/
dual diode module.
Replace the field
fuses at FU1 and FV1
and apply power to
the drive.
Replace the field
board.
No
Replace the
control board.
