Allen-Bradley 20F11ND8P0JA0NNNNN

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 and the state of the external contact. Clear the fault once the external condition is resolved.

Fault 3

Power Loss fault. DC bus voltage dropped below the minimum threshold, indicating an input power interruption or severe voltage sag.
Check incoming AC supply voltage for sags or interruptions. Verify input fuses and contactor. Inspect power wiring connections to the drive.

Fault 4

UnderVoltage fault. DC bus voltage has fallen below the under-voltage trip level during operation.
Verify that input line voltage is within the specified range (380-480 V AC). Check for loose connections or failing input components. Inspect the incoming supply under load conditions.

Fault 5

OverVoltage fault. DC bus voltage has exceeded the over-voltage trip level, typically caused by regenerative energy from a decelerating load.
Increase deceleration time to reduce regenerative energy. Consider adding a dynamic braking resistor or an active front end. Verify that input line voltage is not elevated.

Fault 7

Motor Overload fault. The drive's electronic overload protection has tripped due to sustained overcurrent to the motor.
Check motor load for mechanical binding or overloading. Verify motor overload parameters (FLA setting) are correctly configured. Inspect motor windings for degradation.

Fault 12

HW OverCurrent fault. Output current has exceeded the hardware overcurrent trip level, indicating a short circuit or severe overload condition.
Check motor and output wiring for short circuits or ground faults. Verify that the motor is not mechanically seized. Inspect output power devices; the drive may require repair if the power section is damaged.

Fault 29

Analog Input Loss fault. An analog input signal has fallen below the configured loss-of-signal threshold (e.g., 4 mA signal lost on a 4-20 mA input).
Check the analog signal source and wiring. Verify that the transmitter or controller providing the signal is powered and functioning. Confirm analog input parameter settings match the signal type.

Fault 71

Safe Torque-Off (STO) fault. The STO input circuit has been opened or a discrepancy has been detected in the dual-channel STO inputs.
Verify that the STO input wiring is intact and that the safety circuit is properly energized. Check for wiring faults or a tripped safety relay. If STO activation was unintended, inspect the safety system logic.