TROUBLESHOOTING
OFF-LINE FAILURE
6 - 12
I-E96-322A
®
No servo drive from
the servo amplifiers.
(continued)
Bad connection
to the servo
valve, defective
servo valve.
5. If the connecting cables are open or show an unusually high
impedance, replace the cables.
6. If the cable continuity is good and there is no servo drive output,
check the servo valve and replace if defective.
No LVDT primary
excitation voltage.
Bad LVDT, bad
cable.
Check the LVDT primary.
1. Connect an oscilloscope to the bad LVDT primary at the appro-
priate termination unit or module terminal (LVDT PWR OUT +).
Ground the oscilloscope probe to the system common. Check the
LVDT transformers by doing Steps 2 through 5. Repeat the
procedure for each LVDT primary.
2. Verify that there is an excitation voltage on the primary side of
the LVDT at the selected frequency.
3. Connect the oscilloscope to the return on the bad LVDT primary
at appropriate termination unit or module terminal (LVDT PWR
OUT -). Ground the oscilloscope probe to the system common.
4. Verify that there is a return signal on the primary side of the
LVDT at the selected frequency.
5. If there is no LVDT excitation signal, check the continuity of the
connecting cable.
6. If the connecting cables are open or show an unusually high
impedance, replace the cables.
7. If the cable continuity is good and there is no LVDT excitation,
check the LVDT and replace if defective.
No LVDT secondary
response.
Bad connection
to the LVDT,
bad transformer.
Check the LVDT secondary.
1. Connect an oscilloscope differentially across the bad LVDT
secondary at the appropriate termination unit or module terminals
(LVDT_ S_). Ground the oscilloscope probe to the system
common. Check the servo outputs and return line by doing Steps 2
through 4. Repeat the procedure for each LVDT secondary.
2. Enter a position demand to change the actuator position.
3. Verify that there is a differential voltage on each LVDT
secondary at the selected frequency. The differential voltage will
change during a position demand.
4. If there is no differential voltage on the LVDT secondaries,
check the continuity of the connecting cables.
5. If the cable continuity is good and there is no differential voltage
on the LVDT secondaries, check the LVDT and replace if defec-
tive.
IMHSS03 fails to
calibrate, all process
hardware checks
good, there are no
configuration errors.
IMHSS03
failure.
Replace IMHSS03.
Replacing the
IMHSS03 fails to
correct the problem.
—
Contact Bailey technical support.
Table 6-5. Troubleshooting Off-Line Failures
(continued)
Problem
Cause
Corrective Action
