The Siemens 810T/M economic CNC system is widely used in CNC lathes, milling machines, grinding machines and other machine tools. Due to its simple structure and strong functions, although it is a product from the late 1980s, it is still widely used. The system has a compact structure and strong self-diagnostic ability. It can promptly display alarm numbers and alarm information on the screen for faults in CNC devices, servo devices and machine tools, and stop the corresponding movements. Its alarm system can be roughly divided into several categories: (1) NC system alarms: numbers 1-15 are system alarms, numbers 16-48 are communication port alarms, numbers 100-196 (where * represents axis number, which is the number 0, 1, 2, 3) are servo system alarms, number 2000 is an emergency stop alarm, and numbers 2030-3999 are mainly alarms for errors in program compilation and spindle system faults. (2) PLC alarms: numbers 6000-6063 are not system alarms, but machine tool alarms compiled by the manufacturer for specific machine tools, indicating alarms that occur in the machine tool itself. Alarms 6100-6163 are provided to the PLC programmer, indicating a problem with the PLC program or an error in the PLC itself. (3) PLC operation information: Alarms 7000-7063 are operation prompts designed by the CNC machine tool manufacturer for specific machine tools and are not true alarms. Alarms 6000-6063 and 7000-7063 are detected by the PLC program, and the displayed alarm information comes from the alarm text prepared by the machine tool manufacturer. Our company has many CNC equipment that use Siemens' 810 system. In several years of maintenance practice, we have dealt with the faults that occurred in these equipment many times and accumulated certain experience. The typical fault handling process is introduced as follows. Please click here to download the full text of the article.