Cause: Overcurrent when constant speed running comes when the acceleration ramp-up time is set too short, the motor will draw excessive current to reach the target speed quickly.

oc3 fault invt indicates Overcurrent fault during constant speed running. This means that while the motor is running at a steady speed (not accelerating or decelerating), the drive detected a current spike above its protection threshold.

Troubleshooting Steps:

• Increase the acceleration time parameter in the drive settings. A longer ramp-up will reduce the current demand during startup.
• Ensure the mechanical load is not excessive or jammed.
• Check for any sudden changes or impacts in the load.
• Visually inspect the motor cables for any damage or signs of short circuits.
• Perform an insulation resistance test on the motor windings and the cables to check for ground faults. Use a megohmmeter for this test.
• If possible, use a clamp meter to measure the actual current drawn by the motor during operation and compare it to the drive's and motor's rated current. This can help determine if the load is excessive.