The application scenarios of the encoder and how to resist interference during use

The application scenarios of the encoder and how to resist interference during use?

Encoder is a sensor that outputs physical information such as angle, length, speed and other physical quantities with digital quantities of 0 and 1 with digital information. Because of its high precision, large range measurement, fast response, and digital output characteristics; small size, weight Lightweight, compact structure, easy installation, simple maintenance, reliable work and other excellent characteristics, it has become a popular and indispensable part of today's industrial control system. In today's weird and slow-paced development era, the encoder industry is advancing with the times, bringing more convenient application scenarios to the public and how to resist interference during use?

sport control:

Various products have low protection levels and are very easy to install, suitable for motion control

Synchronous motor asynchronous motor:

Various magneto-optical encoders can work within a common temperature and speed range

Textile machinery:

High vibration and low dust field to ensure accurate speed and position control

Steel machinery: high temperature machinery specially designed for application scenarios in the steel industry, with incremental encoders and absolute encoders with protection levels.

The application scenarios of the encoder and how to resist interference during use?

1. Encoder photoelectric coupling isolation method

In the process of long-distance transmission, a photoelectric coupler is selected to cut off the connection between the control system and the input channel, output channel and input and output channel of the servo drive. The main advantage of photoelectric coupling is that it can accurately suppress peak pulses and various noise interference, thereby greatly improving the signal-to-noise ratio during signal transmission. Although the interference noise has a small voltage amplitude, it has a large energy and can only form a small current. However, the light-emitting diode (LED) of the optocoupler input part works under the current state, and the conduction current is usually 10-15ma. Therefore, even if there is a high-amplitude interference, it will be suppressed because it cannot provide enough current.

2. Encoder twisted pair shielding method;

When the line is transmitted over a long distance, the signal will be affected by interference factors such as electric field, magnetic field, and ground impedance during the transmission process. Compared with coaxial cable, twisted pair cable has less frequency band, but its wave impedance is low, and its ability to resist common mode noise is weak.

Anti-interference planning of power supply system

1. Grouped power supply, such as separating the drive power supply of the executive motor from the control power supply to prevent interference from the equipment building.

2. Choose an isolation transformer. Considering that the high-frequency noise passing through the transformer is not the mutual inductance coupling between the primary and secondary windings, but due to the parasitic capacitance of the primary and secondary windings, a shielding layer is used to isolate the primary of the isolation transformer to reduce its distributed capacitance and improve the immunity. The ability of common mode interference.

3. The noise filter can also accurately suppress the interference of the AC servo drive to other equipment.