A better Cable Manufacturer Focusing on Thermocouple Wire in China

Why choose our Thermocouple Wires

1.Based on over 20 years experience in researching & developing on these wires, our engineering team fully understand all technical requirements for each type wire. through a continous modifcation of our manufacturing equipments, we can make these thermocouple wires fully meets these international standards.

2. Through our scientific management and quality control, we control all manufacturing costs as much as possible, which allow us to provide you a best price of these thermocouple wires in the world.

3. Drawing on our dedicated engineering team and workers in each factory, we are able to provide you several rolls of these thermocouple wires in 6 days on receipt of your purchase order.

4. Through our good colloration with some excellent logistic companies, we are capable of delivering the wire to each corner in the world in 5 working days.

What are main types of thermocouple wire

Based on different thermocouple sensor, and its applied temperature range and its accuracy (class & tolerance), There are many types of thermocouple wire, like theromocouple wire K Type, which has three main types, KX, KCA & KCB; theromocouple wire J Type; theromocouple wire T Type, copper conductor for its positive and CU/NICKEL for its negative; theromocouple wire E Type; theromocouple wire R Type, including RCA & RCB; theromocouple wire S Type, including SCA & SCB; theromocouple wire B Type, the conductor material for both positive and negative is copper; theromocouple wire N Type, including NX & NC. of course, based on its special applications, different types insulation materials, like PVC, glass fiber, Telfon, and silicone rubber can be used on these wire; and in some tough areas, some wires will use some shielded wires and a armoring layer.

The main differences between a thermocouple wire and a thermistor wire :

Firstly, Temperature measurement principle is different
Thermocouple wire: Based on thermoelectric effect. A circuit is formed by connecting two conductors (thermoelectric electrodes) with different compositions at both ends. When the temperatures of the two junction points are different, an electromotive force (thermoelectric potential) is generated in the circuit, and its magnitude is related to the temperature difference between the two junction points. The temperature is determined by measuring the thermoelectric potential.
Thermistor wire: Utilizing the characteristic of metal material resistance changing with temperature. Temperature changes can cause a corresponding positive or negative change in the resistance value of the thermistor, and temperature can be reflected by measuring the resistance value.
Secondly, Signal properties are different :
Thermocouple wire: generates an induced voltage (thermoelectric potential) that varies with temperature.
Thermistor wire : It is a resistor itself, and its resistance value varies with temperature.
Thirdly, Materials are different:
Thermocouple wires are typically made of bimetallic materials.
Thermistor: It is a type of metal resistor.
Fourthm Different Measurement temperature range:
Thermocouple wire: With a wide measurement range, it can generally be used for measuring temperatures between 0-1300 ℃ or even higher, and is commonly used in high-temperature environments.
Thermistor wire: The temperature range for detection is relatively low, commonly around minus 200 ℃ to 500 ℃, and some can reach 700-800 ℃. It is suitable for measuring medium and low temperatures, but the accuracy is usually higher than that of thermocouples within its measurement range.
In termos of unit price:
Thermocouple wires are generally more expensive than thermal resistor wires.
Thermistor wire: The price is relatively cheap.
Wire requirements:
Thermocouple wire : requires compensating wires.
Thermistor wire: Compensation wires are usually not required, but for three wire or four wire thermistors, proper wiring should be taken into account to reduce measurement errors.
Output stability:
Thermocouple wire: The output signal (thermoelectric potential) may not be very stable, especially when there are rapid temperature changes or interference.
Thermistor wire: The output resistance signal is relatively more stable.

Uses of a Thermocouple Wire

Why do many temperature sensors use thermocouple wires?

Firstly, we need to know the principle of thermoelectric effect
What is thermoelectric effect? Thermoelectric effect refers to two different types metal materials , which are pressed together when their contact points are at both ends
When there is a temperature difference, a measurable voltage will be generated simultaneously; The magnitude of this voltage is directly proportional to the temperature difference at the node and analyze the electromotive force characteristics generated by each pair of metal materials; At this time, The curve is known, so by measuring this electromotive force. The temperature can be measured finally.

Why do use these thermocouple wires,

1. The temeperature measurement range is very wide, capable of measuring from near absolute zero degrees; From low temperature to high temperature up to  2700 centi degree , this makes them suitable for many applications. Temperature detection in extreme environments.
2. thermocouples wire are made of special conductors,, usually strong and able to withstand harsh Industrial environment, such as high temperature, vibration, corrosion, etc.
   3. Due to the simple structure of a thermocouple wire, It is usually small in size, as it responds quickly to temperature changes.

More introducstions about a thermocouple wire

1、 Working principle of  a thermocouple wire
A thermocouple wire is a measuring element that converts temperature changes into electrical signals. It is composed of two different materials of wires, usually nickel chromium alloy and copper or conventional alloy wires. When the two ends of a thermocouple wire are at different temperatures, a thermoelectric force is generated. This potential will cause a small current to flow through various parts of the thermocouple, converting temperature changes into electrical signals.
2、 Why can two wires in a thermocouple cable generate current
The two wires in a thermocouple cable, namely nickel chromium alloy wire and copper or conventional alloy wire, are essentially two different materials. There are differences in electronic states between different materials, which can affect the voltage output to the outside world. When there is a temperature difference between the contact points of two wires, the potential difference between the two wires will change accordingly, thus forming a current between the two wires. This current can be detected by instruments in the circuit.
3、 The principle of thermocouple wire generating current
The principle of current generation by thermocouples wire is the thermoelectric effect. Thermoelectric effect is a type of thermoelectric force, which refers to the electromotive force that occurs between electrodes when a battery composed of two different materials is subjected to uneven heating. The typical characteristic of thermocouples is that their thermoelectric effect is very obvious, with high measurement accuracy and sensitivity.
In general, the two wires in a thermocouple wire generate current through thermoelectric and thermoelectric effects. When there is a temperature difference between the two ports of a thermocouple, a potential difference is generated, which leads to the flow of current and converts temperature changes into electrical signals, enabling temperature measurement and control.

How to connect thermocouple wire

As it is known to all, The correct wiring method is crucial when using a thermocouple wire for temperature measurement, as it directly affects the accuracy and stability of the measurement results.

There are usually two wiring methods for thermocouple wires: three wire system and four wire system.

The three wire wiring method is a common wiring method that uses three wires to connect thermocouples and measuring instruments.

The specific steps are as follows: 1. Connect the reference end of the thermocouple wire: Connect the reference end (cold end) of the wire to the reference end of the measuring instrument.

This is usually achieved through a separate wire, which is called a reference wire or compensation wire.

2. Connect the measuring end of the thermocouple wire: Connect the measuring end (hot end) of the thermocouple wire to the measuring end of the measuring instrument. This is also achieved through a single wire.

3. Connect the power supply of the measuring instrument: Connect the power terminal of the measuring instrument to the power supply to ensure that the measuring instrument can work normally.

Attention: Reference wire and measuring wire should use wires of the same conductor material and specifications to ensure measurement accuracy.

The reference wire should be as short as possible to reduce the impact of temperature gradients on the measurement results.

The two ends of the reference wire should be connected to a temperature stable and consistent location to ensure the stability of the measurement results.

The four wire system wiring method is more complex compared to the three wire system, but it can provide better measurement accuracy and stability.

The specific steps are as follows: 1. Connect the reference end of the thermocouple wire: Similar to the three wire system, connect the reference end of the thermocouple to the reference end of the measuring instrument.

But here, the reference end requires two wires, one for transmitting potential signals and the other for compensating signals.

2. Connecting the measuring end of the thermocouple wire: The measuring end also requires two wires, one for transmitting potential signals and the other for transmitting temperature signals.

3. Connect the power supply of the measuring instrument: Similarly, connect the power terminal of the measuring instrument to the power supply.

Attention: The four wire wiring method can effectively eliminate the influence of wire resistance and contact resistance on measurement results, thereby improving measurement accuracy.

Due to the use of more wires, it is necessary to pay attention to the layout and direction of the wires in practical applications to avoid unnecessary interference and errors.

3. Some recautions: Whether using a three wire or four wire wiring method, the following points should be noted: A. ensure that the wire connection is firm and reliable, and avoid loosening or poor contact. B. Use wires made of appropriate conductor material and its size to ensure measurement accuracy and stability.