Assumption 1 - When the CNC lathe is just put into use, when the system is restarted after a power failure, it must return to the reference point. That is, after manually moving each axis out of the non-interference area, return each axis to the reference point. Otherwise, a crash may occur. Therefore, after machining every day, it is best to move the axes of the machine tool to a safe position. At this point, there will be no problem after operation or power failure. Faults caused by external hardware operations are common faults in CNC repairs. It is generally caused by problems with detection switches, hydraulic systems, pneumatic systems, electrical actuators, and mechanical devices. Some of these faults can find the cause of the fault through the alarm information. For general CNC systems, there are fault diagnosis functions or information alarms. Maintenance personnel can use this information to narrow the scope of the diagnosis. For some faults, although the alarm information is displayed, it does not reflect the real cause of the fault. At this time, it is necessary to analyze and solve according to the alarm information and fault phenomenon.
As the reliability of modern CNC systems is getting higher and higher, the failures of the CNC system itself are getting lower and lower, and most of the failures are caused by reasons other than the system itself. The faults outside the system mainly refer to the problems caused by the detection switches, hydraulic components, pneumatic components, electrical actuators, mechanical devices, etc.
External faults of CNC equipment can be divided into soft faults and hard faults caused by external hardware damage. Soft faults are caused by improper operation and adjustment. Such faults mostly occur in the early stage of equipment use or during the adjustment period of equipment users. For the numerical control system, another fault-prone place is the servo unit. Because the movement of each axis is realized by the servo unit controlling the servo motor to drive the ball screw. Use rotary encoder for speed feedback and grating ruler for position feedback. Generally, the fault-prone place is the drive module of the rotary encoder and the servo unit. There are also individual system confusions caused by power supply reasons. Especially for those systems with computer hard drives to save data.