Interference of the hottest CNC equipment

The interference problem of numerical control equipment

the so-called interference is the influence of different user groups' noise other than the useful signal on the system. Interference is mainly divided into internal interference and external interference

internal interference includes:

1, crosstalk between signals

2, unreasonable layout of components and poor quality of components

3. Coupling of adjacent circuits

4, digital and analog effects

5. Parasitic oscillation

external interference mainly includes:

1. Electromagnetic interference, including the connection and disconnection of electrical equipment near the close system, passing vehicles, electromagnetic waves, etc

2. Influence of power supply fluctuation

3. Environmental interference, vibration, temperature and humidity, etc

internal interference is related to the manufacturing of CNC system, which can be eliminated and suppressed as much as possible through careful design. Imported machine tools can do this, while external interference is random, independent of NC structure. Generally, it is difficult to limit the interference source, and preventive measures can only be taken for specific situations

external interference coupling modes mainly include:

1, common impedance coupling mode. Due to the different grounding points of the ground wire system, it inevitably took 7 years to generate the interference of common impedance coupling in a bay along the coast of Cancun, a resort in southeast Mexico

2. Electrostatic coupling mode. It is the interference of the electric field into the common line through capacitive coupling

3. Electromagnetic induction coupling mode. Due to the mutual inductance magnetic field between the power line and the signal line, the closed loop in the NC system generates the induced potential, that is, the interference voltage

4. Leakage coupling mode: mainly because the insulation resistance between adjacent conductors or some coupling capacitors decreases, the interference is transmitted to the signal line through the resistance between conductors

the interference source interferes with the equipment through the interference path, so the suppression of interference also starts from the following three aspects

1. Filtering, damping, shielding, decoupling and other means are used to reduce the effect of interference sources

2. Adopt isolation, shielding, impedance matching, balanced wiring, circuit decoupling and other "three innovations" for interference paths: it refers to product innovation, technological innovation and innovative measures in the field of utilization

3. For disturbed equipment, various methods such as improving signal-to-noise ratio, increasing switching time, improving power level, and implementing power supply and signal filtering can be adopted