1. Selection of compensation wire
一定要根据所使用的热电偶种类和使用的场合进行正确选择。 The compensation wire must be properly selected according to the type of thermocouple used and the occasion of use. ，根据使用场合，选择工作温度范围。 For example, the K-type couple should select the compensation wire of the K-type couple, and select the operating temperature range according to the application.
Generally, the working temperature of KX is 20 ~ 100 ℃, and the wide range is 25 ~ 200 ℃. The error of normal grade is ± 2.5 ℃, and the precision grade is ± 1.5 ℃.
2. Contact connection
As close as possible to the two contacts of the thermocouple terminal, try to keep the two contacts at the same temperature. Keep the temperature as consistent as possible with the connection end of the meter cable. Where there is a fan in the meter cabinet, protect the contact point so that the fan does not blow directly to the contact point.
3. Use length
Because the signal of the thermocouple is very low, it is a microvolt level. If the distance used is too long, the attenuation of the signal and the interference of strong electricity in the environment can distort the signal of the thermocouple, resulting in inaccurate measurement and control temperature. When in control
Temperature fluctuations will occur.
According to our experience, it is usually better to control the length of the thermocouple compensation wire within 15 meters. If it exceeds 15 meters, it is recommended to use a temperature transmitter to transmit the signal. Temperature transmitter converts the potential value corresponding to temperature to DC
Electric transmission, strong anti-interference.
一定要远离动力线和干扰源。 Compensation wiring must be kept away from power lines and sources of interference. Wherever you ca n’t avoid crossing, try to use a cross method instead of parallel
5.Shield compensation wire
In order to improve the anti-interference performance of the thermocouple connection line, a shielded compensation wire can be used. The effect is better for occasions with many interference sources on site. However, the shielding layer must be strictly grounded, or the shielding layer will not only play a shielding role.
But enhanced interference