Common failures of CNC machining center servo system

As we all know, the servo system of the machining center is a system that provides power to the machine tool. Without the servo system, the machining center cannot process the workpiece. Therefore, the servo system is very important in the machining center. When the servo system fails, the entire processing production must be stopped. Today, I will introduce the common faults of the machining center servo system.

The fault form of the servo system of the machining center includes the alarm indicator light and fuse blown on the speed unit in the CNC and the alarms such as trip switches for various protection. The meaning of the warning light varies with the design difference of the speed control unit, generally there are the following:

  • 1. The large current causes the machine tool to alarm, and there are generally two possibilities for the high current alarm, that is, the large current alarm caused by the damage of the power driving element on the CNC speed control unit of the machining center and the short circuit.
  • 2. The high voltage will also cause the machine tool to alarm. There are generally three possibilities for the high voltage alarm, which may be that the CNC input voltage of the machining center exceeds 10% of the rated value, or the insulation performance in the servo motor is reduced, or High voltage caused by the line of the speed control unit of the machining center.
  • 3. The low voltage causes the machine tool to alarm. The occurrence rate of the machining center is very rare. This may happen because the input voltage is less than 85 percent of the rated value, or the power supply connection is poor.
  •  4. The feedback route for detecting the speed is broken, which leads to an alarm. If this happens, it is a false alarm, because there is no problem in the airport, and there is a problem with the detection and feedback system. Most of this alarm is the speed feedback line of the CNC servo motor of the machining center Broken or caused by poor contact of its detection feedback line.
  • 5. The protection switch starts to alarm. The protection switch is a device to protect the machine tool. For example, high voltage will burn some components and other emergency measures that the machine tool cannot control. When these conditions are encountered, the protection switch will start to avoid unnecessary The component is damaged, similar to a safe stop.
  • 6. Overload alarm, the cause of the overload alarm is that the CNC machine load of the machining center is abnormal, or the upper limit of the motor current on the speed control unit is set too low. The permanent magnet on the permanent magnet motor can also cause an overload alarm. If the motor without a brake in the machining center is not loaded with a hand or the shaft is very laborious, it means that the permanent magnet is completely off.
  • 7. The fuse on the CNC speed control unit of the machining center is blown or the circuit breaker is tripped.