Dingzun Type K 2 X 1 / 0.65mm2 Thermocouple Wire For Temperature Control

Because when using thermocouple temperature measurement, the reference end temperature of the thermocouple must be kept constant, otherwise the measurement error introduced in the temperature measurement will be a big variable, will affect the accuracy of temperature measurement.

However, in field use, the reference end of the thermocouple is usually near the high temperature heat source, and the reference end of the thermocouple cannot be stabilized by the heat source. Therefore, the reference end of the thermocouple must be moved to the place where the temperature is more stable. The compensation wire is made of the same metal material as the thermocouple, or the thermoelectric property (thermal power) is the same as the connected thermocouple within the specified temperature range (generally 0 ~ 100℃), and it is made of cheap metal material which is easy to obtain.

It can extend the role of the thermocouple in temperature measurement or be used as the connecting wire between the thermocouple and the instrument (such as electronic potentiometer). Therefore, the thermocouple in use to connect the compensation wire. But it cannot eliminate the influence of the reference end temperature is not zero, so the reference end temperature should be corrected to 0℃ in use.

The following points should be noted when using compensation wires:

1. All kinds of compensation wires can only be used with the corresponding type of thermocouple, that is, all kinds of thermocouples and the compensation wires used together, in the specified temperature (such as 0 ~ 100℃) within the range of heating power must be consistent.

2. When the compensation wire is connected with the thermocouple instrument, the two pairs of connection points should be at the same temperature, and the positive and negative poles should not be connected wrong. Compensation wire is equivalent to a thermocouple in a certain temperature (0 ~ 100℃) range, so its current is also from the positive terminal through the reference terminal flow to the negative terminal, so when connected with the thermocouple, the positive pole of the compensation wire should be connected to the positive pole of the thermocouple, the negative pole should be connected to the negative pole of the thermocouple. If the polarity is reversed, it will not only lose the function of the compensation wire, but will offset a part of the thermocouple's thermal power, so that the indicator temperature of the instrument is low.

3. The temperature of compensation wire and thermocouple connection point shall not exceed the specified temperature range.

4. The diameter of the compensation wire should be selected according to the different requirements of the instrument. For example, the compensation wire connected with the moving coil instrument can be selected with thicker wire diameter, so that its resistance value is smaller, so as not to affect the external resistance value of the instrument.

5. The thermocouple with a long line can use multiple and thicker compensation wires for easy installation and laying.
Compensation wire should be divided into extension type and compensation type because of different core wire alloy material:

Extended type compensation wire: there are NX , KX, EX , JX, TX . Compensation wire: SC and RC , KC , NC and so on.

When to use extended or compensating wire:
Extension type: compensation wire cold end of the environment is greater than 100 degrees or less than 0 degrees, in order to measure the accuracy, only use the extension type compensation wire, but the price is more expensive.

Compensation type: Economical, but the cold end temperature must be in a relatively stable place.
Compensation wire must have the characteristics:
1. Stable thermoelectric characteristics, good electrical insulation performance, long service life.
2. Soft, good bending performance, easy to use.
3. The coating material is stable and reliable, with certain temperature resistance and cold resistance.