The fault forms of CNC machining center servo system include alarm light on speed unit, fuse and jump switch for various protection. The meaning of alarm light varies with the design of speed control unit. Generally, there are the following kinds:
1. High current causes machine tool alarm. In general, there are two possibilities for high current alarm, that is, the damage of power drive components in NC speed control unit of machining center and the high current alarm caused by short circuit.
2. High voltage will also lead to machine tool alarm. There are three kinds of situations where high voltage alarm occurs. It may be that the CNC input voltage of the machining center exceeds 10% of the rated value, or the insulation performance of the servo motor decreases, or the high voltage caused by the circuit of the speed control unit of the machining center.
3. Too low voltage leads to machine tool alarm. The probability of this happening in the machining center is very small. It may be that the input voltage is lower than 85% of the rated value, or the power connection is not good.
4. Feedback line break of detection speed leads to alarm, which is an error alarm, because the airport is not a problem, and there are problems in the detection and feedback system. Most of these alarms are caused by speed feedback line break of CNC servo motor in machining center or bad contact of its detection and feedback line.
5. Protective switch start alarm. Protective switch is a kind of device to protect machine tools. For example, high voltage will burn some components and other emergency measures that machine tools can not control. When encountering these situations, the protective switch will start to avoid unnecessary component damage, similar to safety stop and so on.
6. Overload alarm, the causes of overload alarm are abnormal load of CNC machine in machining center, or too low upper limit of motor current in speed control unit. Permanent magnet shedding on permanent magnet motor can also cause overload alarm. If the CNC motor without brake is idle, it is hard to rotate by hand or to rotate the axis, that means permanent magnet shedding completely.
7. Fuse burning or circuit breaker tripping on CNC speed control unit of CNC machining center.
