Troubleshooting
table (cont’d)
Problem (and system
status numbers)
Possible cause
Action
Bus Undervoltage (E1)
VBus < VBusThresh
VBusThresh is set too high.
VBus is low because bus
AC power is low. Check
J1-1, J1-2, and J1-3.
Ambient temperature too
low (E2)
Ambient temperature
< 0
°
C
Measure temperature in
control cabinet. Condition
if necessary.
Internal failure.
Return to factory for repair.
Encoder commutation
alignment failure (E3)
Not enough current to lock
the motor shaft to proper
position within 1 second.
Check IlmtPlus and
IlmtMinus.
If vertical load, reduce load
or increase motor/drive.
Verify motor brake releases
properly.
Internal failure.
Return to factory for repair.
Incompatible 950IDE (E4)
950IDE version is
incompatible with drive’s
NV memory version.
Verify that FWV and
950IDE version are the
same. If FWV = 200, then
950IDE should be version
2.0 or higher.
Control card hardware not
compatible with drive
software version (E5)
Resolver wiring error.
Remove J2 and J3
connectors. Cycle power.
If fault is now a “2”, then
correct resolver excitation
wiring.
Internal failure.
Return to factory for repair.
MA950
5 - 9
