How to connect the three wires of a thermocouple

1. The basic principle of thermocouples
Thermocouples are a commonly used temperature measuring instrument that utilizes the thermoelectric effect to measure the temperature of an object. Thermocouples are composed of two different metal wires, which are connected to the thermometer through connecting cables. According to the thermoelectric effect, when there is a temperature difference between the connection points of two types of wires, there will be a potential difference between the wires, which can be used to measure temperature.

2. Wiring method for thermocouples
Thermocouples generally have three wires, two of which are thermocouple wires and the other is a protective grounding wire. The correct method of wiring is crucial for accurate measurement of thermocouples.

Firstly, connect the two wires of the thermocouple to two wires of the same color on the colored cable. Among them, the red wire is the positive electrode, which is connected to the red wire on the colored cable; Connect the negative electrode wire to the colored cable wire.

Secondly, connect the protective grounding wire of the thermocouple to the protective grounding wire on the colored cable, usually a silver or copper wire.

Afterwards, use insulating tape to secure the connection of the wire to ensure a secure and reliable connection.

3. Precautions for thermocouples
When wiring, attention should be paid to the following points:

The wiring of thermocouples should be kept dry to avoid contact with moisture or environments with high humidity.

Secondly, the wiring terminals of the grounding wire should be well grounded to ensure grounding safety.

Thirdly, the wires of thermocouples should be kept neat to avoid being too tangled or hanging on objects.

4. Application fields of thermocouples
Thermocouples are widely used in temperature measurement in various fields, such as industrial manufacturing, medical instruments, scientific research experiments, etc. It has the characteristics of wide measurement range, high measurement accuracy, and durable structure, and is widely recognized and applied in the field of temperature measurement and control.

In short, correct wiring is the key to measuring temperature with thermocouples, and only reasonable connections can obtain accurate and reliable temperature data.