The emergency stop button of CNC lathe is out of order.

Check the status of PLC, especially according to the operation of emergency stop and overtravel release related programs (that is, observe the dynamic changes of ladder diagram after pressing emergency stop and overtravel release, judge whether the external button is out of order or the line is out of order, check whether the ladder diagram can act when pressing the related button, and check other related actions). Generally speaking, the failure of emergency stop will not lead to the cancellation of overtravel, and it will also fail. It is more accurate to judge according to the state of I/O point of PLC.