The vertical and horizontal machining center(CNC system is FANUC 0MC) shows “Not Ready” alarm after turn on the power, the servo drivers could not be launched.

Check the machine electric diagram and PLC program, then found the “Emergency Stop” signal is on.

Problem is the Vertical/horizontal Switch head is not in position, which caused the “Emergency stop”.

The Vertical/Horizontal switch head’s positioning signal is “0”, the non contact switch is broken, change it the problem is solved.