7122 Motor Overload Fault in ABB ACS580 Drive

7122 Motor Overload in the ABB ACS580 Drive indicates that the motor current has exceeded the motor overload protection limit. The drive continuously monitors the motor current and calculates the motor's thermal condition. When the calculated motor temperature exceeds the allowable limit, the drive generates Fault 7122 to protect the motor from overheating and possible insulation damage.

This fault generally indicates a problem with the motor load, motor sizing, or overload protection settings, rather than an internal drive hardware failure.

Possible Causes

• Motor overloaded.
• Mechanical load is too high.
• Motor stalled or jammed.
• Incorrect motor overload protection settings.
• Motor rated current parameters set incorrectly.
• Motor capacity too small for the application.
• Prolonged operation above rated current.
• Excessive start/stop cycles.
• Motor cooling fan failure.
• Poor motor ventilation.
• High ambient temperature.
• Worn or seized motor bearings.
• Driven equipment mechanical fault.

Solutions

1. Check the motor and the machinery coupled to the motor for overload.
2. Adjust the parameters used for the motor overload function:
   • 35.51
   • 35.52
   • 35.53
   • 35.55
   • 35.56
3. Verify that the motor nameplate data is correctly programmed into the drive.
4. Reduce the mechanical load if necessary.
5. Check the motor cooling fan and ventilation.
6. Allow the motor to cool before restarting.
7. Reset the fault after correcting the cause.

Additional Information

The ABB ACS580 uses an electronic motor thermal protection model to estimate motor temperature based on operating current and time.

Fault 7122 is generated when the calculated motor thermal capacity exceeds the configured protection limit.

According to ABB, the recommended corrective actions are to:

• Check the motor and driven machinery for overload.
• Adjust the motor overload protection parameters (35.51–35.53 and 35.55–35.56).

Unlike an Overcurrent Fault, which reacts instantly to excessive current, 7122 Motor Overload is a thermal protection fault that develops over time due to sustained overload.

Common Symptoms

• Drive displays 7122 Motor Overload.
• Motor becomes excessively hot.
• Fault occurs after the motor has been running for some time.
• Motor stops unexpectedly under heavy load.
• Reduced machine performance.
• Frequent overload trips during continuous operation.
• High motor current before the trip.
• Motor may emit excessive heat or unusual noise.
• Drive cannot restart until the fault is reset.
• Repeated trips if the overload condition remains.

Recommended Troubleshooting Sequence

1. Verify that the fault is 7122 Motor Overload.
2. Disconnect power and follow lockout/tagout procedures if maintenance is required.
3. Check the motor and driven machinery for mechanical overload.
4. Measure the motor current and compare it with the motor's rated current.
5. Verify the motor nameplate data programmed in the drive.
6. Check and adjust Parameters 35.51–35.53 and 35.55–35.56 as required.
7. Inspect the motor cooling fan and ventilation.
8. Check for worn bearings or mechanical binding.
9. Allow the motor to cool completely.
10. Reset the fault and test the system under normal operating conditions.

7122 Motor Overload Check Table

Check Point	Action
Motor load	Check for overload
Driven machinery	Inspect for mechanical binding
Motor current	Compare with rated current
Parameters 35.51–35.53	Verify overload protection settings
Parameters 35.55–35.56	Verify overload protection settings
Motor nameplate data	Confirm correct programming
Motor cooling	Inspect fan and ventilation
Motor bearings	Check for wear or seizure
Ambient temperature	Ensure adequate cooling conditions
Drive operation	Verify normal operation after repair

Preventive Maintenance Tips

• Monitor motor current during normal operation.
• Program the correct motor nameplate data into the drive.
• Inspect the driven machinery regularly for excessive load.
• Keep the motor cooling fan and ventilation openings clean.
• Avoid prolonged operation above the motor's rated current.
• Use appropriate overload protection settings for the application.
• Lubricate motor bearings according to the manufacturer's recommendations.
• Maintain adequate airflow around the motor and drive.
• Record recurring 7122 Motor Overload faults to identify long-term loading problems.
• Follow ABB preventive maintenance recommendations for the ACS580 drive and motor.

Proper inspection of the motor load, driven machinery, motor overload protection parameters (35.51–35.53 and 35.55–35.56), motor cooling, and motor nameplate settings will help prevent recurring 7122 Motor Overload faults in ABB ACS580 drives, ensuring reliable motor protection, improved system performance, and long-term equipment reliability.