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Rockwell Automation Publication 520-UM002D-EN-E - January 2023 117
Chapter 7 Troubleshooting
FLT S10 – INV OVERCURRENT Inverter Overcurrent Fault
Inverter current has exceeded the
instantaneous current limit (determined by
hardware).
• Check motor power cable for shorts.
• Verify that motor windings are not
shorted.
• Verify motor power wire gauge.
• Operate within the continuous power
rating.
• Reduce acceleration times.
FLT S11 – INV OVERTEMP FL
Inverter Overtemperature Factory Limit
Fault
The measured inverter temperature has
exceeded the factory set temperature
limit.
• Modify the command profile to reduce
speed or increase time.
• Reduce drive ambient temperature.
• Verify that airflow through drive is not
obstructed.
FLT S13 – INV OVERLOAD FL
Inverter Thermal Overload Factory Limit
Fault
The thermal model for the power
transistors indicates that the temperature
has exceeded the factory set thermal
capacity rating of 110%.
Modify the command profile to reduce
speed or increase time.
FLT S16 – GROUND CURRENT Ground Current Factory Limit Fault
The sensing circuitry in the power stage
has detected excessive ground current.
• Check motor power wiring; check power
cable for shorts.
• Replace motor if the fault persists.
FLT S23 – AC PHASE LOSS AC Single Phase Loss Fault
A single AC input phase was lost while the
drive was enabled.
Check AC input voltage on all phases.
FLT S25 – PRECHARGE FAILURE Pre-charge Failure Fault
The pre-charge circuit monitoring
algorithm detected that the DC bus did not
reach a factory set voltage level after
charging for a period of time.
• Check AC input voltage on all phases.
• Check input power wiring.
• Replace drive if fault persists.
FLT S29 – BUS OVERLOAD FL
Bus Regulator Thermal Overload Factory
Limit Fault
The shunt thermal model has exceeded its
factory set thermal capacity limit.
• Modify the duty cycle of the application.
• Add external shunt for additional
capacity.
• Add capacitor module if needed.
FLT S34 – BUS UNDERVOLT UL Bus Undervoltage User Limit Fault
DC Bus voltage level is below the user set
limit as given by Bus Undervoltage User
Limit.
• Verify voltage level of the incoming AC.
• Monitor AC power source for glitches or
line droop.
• Install UPS on AC input.
• Decrease Bus Undervoltage UL attribute
value.
FLT S35 – BUS OVERVOLT FL Bus Overvoltage Factory Limit Fault
DC Bus voltage level is above the factory
set limit as determined by the configured
input voltage.
• Change the deceleration or motion
profile of all drives that are connected to
the DC bus.
• Unplug the shunt connector and
measure the resistance of the shunt.
• Replace drive if shunt resistor is open.
FLT S37 – BUS POWER LOSS Bus Power Loss
DC Bus voltage level is below the Bus
Power Loss Threshold for more than the
timeout period specified Bus Power Loss
Time value.
• Verify voltage level of the incoming AC.
• Monitor AC power source for glitches or
line droop.
• Install UPS on AC input.
FLT S41 – FDBK SIGNAL NOISE FL Feedback Signal Noise Fault
Noise induced A/B channel state changes
(illegal states) from a feedback device
were detected by the drive. Specifically,
the number of these noise events that
have occurred on this channel has
exceeded the Feedback Noise Factory
Limit. The offending feedback channel
number is encoded in the associated
Fault/Alarm Sub Code.
• Check motor feedback cable and
connector.
• Cycle power.
• Check feedback shield connection.
• Reduce shock and vibration to motor.
• Replace motor if fault continues.
• Verify all HTL/TTL DIP switches on the
25-ENC-2/B encoder are set in the same
position.
FLT S43 – FDBK SIG FL
Feedback Signal Loss Factory Limit
Fault
The absolute value of the differential A/B
signals is below a factory limit.
• Check motor feedback cable and
connector.
• Check that motor power cable and
feedback wire shields are secured
correctly.
• Check that motor frame is grounded
correctly.
FLT S50 – HARDWARE OVERTRAVEL
POSITIVE
Hardware Overtravel Positive
Axis moved beyond the physical travel
limits in the positive direction and
activated the Positive Overtravel limit
switch.
•Check wiring.
• Verify motion profile.
• Verify axis configuration in software.
FLT Sxx Fault Codes (Continued)
Exception Code on Display Exception Text Problem Possible Solutions