Allen-Bradley 20G1ANE077AN0NNNNN

Common Fault Codes

Fault 2

Auxiliary Input fault. A digital input configured as an auxiliary input has opened, indicating an external fault condition.
Check the external device or circuit connected to the auxiliary input. Verify wiring integrity and confirm the external device is operating correctly before resetting the fault.

Fault 3

Power Loss fault. The drive detected a loss of input AC power or an input phase loss condition.
Check incoming AC supply voltage on all three phases. Inspect input fuses, contactors, and wiring. Verify that input voltage is within the drive's rated specification before restarting.

Fault 4

Undervoltage fault. DC bus voltage has dropped below the minimum threshold, typically caused by low input voltage or a momentary power dip.
Measure input line voltage and verify it is within specification. Check for loose connections on the input terminals. If the fault is intermittent, investigate upstream power quality issues.

Fault 5

Overvoltage fault. DC bus voltage has exceeded the maximum allowable level, often caused by regenerative energy from a decelerating load.
Increase deceleration time to reduce regenerative energy. Verify that a dynamic braking resistor or active front end is installed and functioning if the application requires rapid deceleration.

Fault 7

Motor Overload fault. The drive's electronic overload protection has tripped due to sustained overcurrent conditions in the motor.
Check the motor for mechanical overload, blocked rotor, or excessive friction. Verify motor overload parameters are configured correctly for the connected motor's nameplate data.

Fault 12

HW Overcurrent fault. The drive output current has exceeded the hardware overcurrent trip level, indicating a severe overcurrent event.
Check for a short circuit in the motor cable or motor windings. Inspect output terminals and cable insulation. Verify that the motor is not stalled and that load conditions are within drive ratings.

Fault 33

Auto Restart Tries fault. The drive has exceeded the configured number of automatic restart attempts following a fault condition.
Identify and resolve the root cause of the original fault that triggered the restart attempts. Reset the drive manually after correcting the underlying issue.

Fault 81

Safe Torque-Off (STO) fault. The safe torque-off function has been activated or a discrepancy has been detected in the STO input signals.
Verify that the STO input signals are correctly wired and that the safety circuit is in the correct state. Check the safety relay or safety controller output. If STO was unintentionally activated, investigate the safety circuit for wiring faults or component failure.