The plant has two identical production lines that were installed at the same time. They make heavy use of robotics and other automation, and thus contain quite a bit of electronics.
Line A has almost no problems — ever. Line B shuts down almost daily with some problem or another. The three most common failures are: dead circuit boards, drive motors with spun bearings, and dead servo motors.
Maintenance on these lines is identical, except on Line B a power analyzer ha