Q1: What is a thermocouple?
A1: A thermocouple is a commonly used temperature-measuring component in a temperature-measuring instrument. It directly measures the temperature and converts the temperature signal into a term electromotive force signal, which is converted into the temperature of the measured medium by an electric meter (secondary meter). The shape of various thermocouples is often very different due to the needs, but their basic structure is almost the same, usually composed of the hot electrode, insulating sleeve protection tube and junction box, etc., usually with a display instrument, recording instrument and electronic adjustment Used in conjunction with the device.
Q2: What is a K-type thermocouple used for?
A2: As a transmitter for measuring temperature, industrial K-type thermocouples are usually used in conjunction with display instruments, recording instruments and electronic regulators. It can directly measure the surface temperature of liquid, vapor and gaseous media and solids ranging from 0°C to 1000°C in various production processes.
Q3: How does a thermocouple work?
A3: A thermocouple is the connection of two different conductors or semiconductors into a closed circuit. When the temperature of the two junctions is different, an electromotive force will be generated in the circuit. This phenomenon is called the hot spot effect, also known as the Seebeck effect. The end directly used to measure the temperature is called the working end, and the other end is called the cold end. The cold end is directly connected to the instrumentation or supporting equipment, and the display instrument will point out the electromotive force generated by the thermocouple.
Tips: Thermocouple Troubleshooting
|The thermoelectric potential is larger than the actual value (the indication value of the display instrument is too high).
|The display instrument does not match the thermocouple.
|Replace the thermocouple to match.
|The thermocouple is not compatible with the compensation wire.
|Replace the compensation wire to match the thermocouple.
|There is a DC interference signal entering.
|Eliminate DC interference.
|Thermal EMF output is unstable.
|Poor contact between thermocouple terminal and thermode.
|Tighten the terminal post screws.
|The insulation of the thermocouple measurement line is damaged, causing intermittent short circuit or grounding.
|Find the point of failure and repair the insulation.
|The thermocouple is not installed firmly or external vibration.
|Tighten the thermocouple, eliminate vibration or take shock-absorbing measures.
|The thermode will not break.
|Repair or replace thermocouple.
|External interference (AC leakage, electromagnetic field induction, etc.).
|Find out the source of interference and take shielding measures.
|Thermocouple thermoelectric potential error is large.
|Improper installation of thermocouple.
|Change the installation location.
|There is dust on the surface of the protection tube.
|Remove dust from the thermocouple.