Allen-Bradley 20G1ALD740AN0NNNNN

Common Fault Codes

Fault Code 2

Auxiliary Input fault. An external device connected to the auxiliary input has triggered a fault condition.
Check the wiring and status of the device connected to the auxiliary input terminal. Clear the fault once the external condition is resolved and the input is restored.

Fault Code 3

Power Loss fault. Input power to the drive was lost or dropped below the acceptable threshold during operation.
Verify incoming AC supply voltage at all three phases. Check fuses, contactors, and upstream supply. Restore stable input power before restarting.

Fault Code 4

Undervoltage fault. DC bus voltage has dropped below the minimum operating level.
Check input line voltage for sags or phase loss. Inspect precharge circuit and DC bus capacitors. Verify supply capacity is adequate for the load.

Fault Code 5

Overvoltage fault. DC bus voltage has exceeded the maximum allowable level, typically caused by regenerative energy from a decelerating load.
Increase deceleration time in drive parameters. Consider adding a dynamic braking resistor or regenerative unit. Check for overhauling load conditions.

Fault Code 7

Motor Overload fault. The drive's electronic overload protection has detected sustained overcurrent conditions indicating motor thermal overload.
Check motor load for mechanical binding or excessive load. Verify motor overload parameters are correctly configured for the connected motor nameplate data.

Fault Code 12

HW Overcurrent fault. Output current has exceeded the hardware overcurrent trip threshold.
Check for short circuits in motor cabling or motor windings. Verify that acceleration time is not too short for the connected load inertia. Inspect output power devices.

Fault Code 25

Drive Overtemperature fault. The drive heatsink or internal temperature has exceeded the allowable operating limit.
Check that cooling fans are operational and airflow is unobstructed. Verify ambient temperature is within specification. Clean heatsink fins and air filters. Check for adequate enclosure ventilation.

Fault Code 81

Communication Loss fault. The drive has lost communication with the controlling device over the configured network (e.g., EtherNet/IP, DeviceNet).
Check network cabling and connectors. Verify the controller is active and the network is functioning. Review communication timeout parameters in the drive configuration.