The numerical control system is the abbreviation of the digital control system. The English name is (Numerical Control System), which performs part or all of the numerical control functions according to the control program stored in the computer memory, and is equipped with a dedicated computer system of the interface circuit and the servo drive device. By using digital commands composed of numbers, words and symbols to realize the motion control of one or more mechanical devices, it usually controls the mechanical quantity and the switching amount such as position, angle and speed.
CNC systems and related automation products are mainly for CNC machine tools. CNC machine tools are mechatronic products formed by the penetration of new technologies represented by numerical control systems into the traditional machinery manufacturing industry: CNC machine tools greatly improve the accuracy, speed and efficiency of parts processing.
Common faults and causes:
Position loop: This is the key link for the CNC system to issue control commands and compare with the feedback value of the position detection system to further complete the control task. It has a high frequency of operation and is connected to peripherals, so it is prone to failure.
Common faults are:
1-position control loop alarm: It may be that the measurement loop is open; the measurement system is damaged, and the position control unit is damaged internally.
2 Movement without instruction, may be excessive drift, positive feedback, position control unit failure; measurement component damage.
3 measuring component failure, generally showed no feedback value; the machine tool can not return to the reference point; the high-speed leakage pulse can cause the alarm may be caused by the grating or the read head is dirty; the grating is broken.
Servo drive system: The servo drive system is associated with the power grid, mechanical system, etc., and it is always in a state of frequent start and run during operation, so this is also a part with more faults.
Power section: The power supply is the energy support part that keeps the system working properly. The direct result of failure or failure is the system shutdown or the destruction of the entire system. Generally speaking, in Europe and the United States, there are few such problems. In terms of design, there are not many factors in consideration. However, due to the large fluctuations in power supply and poor quality in China, there are hidden interferences such as high-frequency pulses, plus artificial Factors (such as sudden power failure, etc.). These causes can cause power failure monitoring or damage. In addition, part of the numerical control system operation data, setting data and processing programs are generally stored in the RAM memory, and after the system is powered off, it is maintained by a backup battery or a lithium battery of the power source. Therefore, the downtime is relatively long, and the power supply or the memory may be lost, and the system may not operate.