Cause : Motor cable overload comes when calculated motor cable temperature has exceeded warning limit. A motor cable overload fault "4000" in an ABB ACS880 drive indicates that the drive has detected excessive current in the motor cables, which can be caused by various issues such as incorrect cable sizing, poor connections, or a problem with the motor itself. 

Steps to Diagnose and Resolve Motor Cable Overload Fault

1. Fault Identification

• Fault Code: Check the drive's display or control panel for the specific fault code related to motor cable overload. This code will help in pinpointing the exact nature of the problem.

2. Initial Checks

• Visual Inspection: Perform a thorough visual inspection of the motor cables and connections. Look for signs of overheating, damage, loose connections, or improper installation.
• Cable Sizing: Ensure that the motor cables are properly sized for the current they need to carry. Undersized cables can overheat and cause overload faults.

3. Electrical Testing

• Current Measurement: Use a clamp meter to measure the current flowing through each phase of the motor cable. Compare these readings with the motor's rated current.
• Insulation Resistance Test: Check the insulation resistance of the motor cables to ensure there are no shorts or leakage paths that could contribute to the fault.

4. Motor and Drive Configuration

• Motor Nameplate Data: Verify that the drive settings match the motor nameplate data, including rated current, voltage, and frequency.
• Parameter Settings: Review and adjust relevant drive parameters to ensure they are set correctly for the motor and application.
  • Motor Overload Protection: Check parameters related to motor overload protection and ensure they are set correctly.
  • Current Limits: Verify the current limit settings to ensure they are appropriate for the motor and application.

5. Load Conditions

• Check the Load: Ensure that the load on the motor is within its rated capacity. An overloaded motor can draw excessive current and trigger an overload fault.
• Mechanical Issues: Inspect the motor and connected equipment for mechanical issues that could cause excessive load, such as binding, misalignment, or obstructions.