A5001 alarm code in ABB ACS550 drive
A5001 code on an ABB ACS550 drive indicates "drive not responding". This means communication failure between the control panel and the main control board. Common Causes and Troubleshooting: Communication Loss: The control panel cannot communicate with the main processor, often due to a damaged CPU. Power Issue: Lack of 3.3V DC power at connector X3 on the WINT1011C power board. Loose Connections: Check that the control panel is properly seated on the drive. Power Cycle: Attempt to power cycle the drive to clear the fault. Hardware Failure: If the error persists, it usually requires replacing the control board or the entire drive unit.