Hi guys,

So we have an ABB ACS580 drive running a 90KW motor. Suddenly after a normal production startup we realized that our drive is not increasing output frequency and is not going above 45hz. According to the speed reference from PLC it should've been running at 75hz but it wasn't going above 45hz. Then an expert came and he did just one thing. He disabled the parameter 30.31 (Undervoltage control) and everything went fine. Now i don't understand that why the drive has been running fine for months with this parameter previously enabled? And how disabling this it got ok? There are two other machines with the same drive and control system. This parameter is enabled in both of them but they are still running fine.