The A5012 code on an ABB ACS (including ACS150) drive indicates a "DIR LOCK" alarm. This means there's an issue with changing the direction of the motor.

Here's a breakdown of the A5012 alarm:

• Cause: An attempt was made to reverse the motor direction when it's not allowed by the drive settings.
• Possible Reasons: The drive might be programmed to only allow the motor to run in one direction.
• Enable change of direction. See parameter 1003 DIRECTION