Infrared thermometers are widely used in refractory factories due to their high temperature measurement accuracy. Among them, there are many temperature measurement points in the key tunnel kiln. Infrared thermometers have the characteristics of many temperature measurement points and long continuous working hours. If the temperature parameters are not well controlled, it will bring significant economic losses to the production enterprise. Therefore, choosing a suitable temperature measurement method is an important link to ensure the normal operation of the kiln. There are two traditional temperature measurement methods for tunnel kilns: one is to use thermocouples to measure temperature. This method is characterized by high temperature measurement accuracy and can be connected to recorders or control systems for closed-loop control. Automatic recording, and the influence of human factors, the authenticity is poor. Application of HD series infrared thermometer can effectively overcome the above shortcomings. The instrument has high measurement accuracy (up to ±0.5 percent ), and can output electrical signals like a thermocouple for automatic recording and control. It also has the advantages of long service life (more than five years), simple operation, and small human error. Therefore, HD series infrared thermometer is an ideal temperature measuring instrument for high temperature tunnel kiln. In the application of HD series infrared thermometers in tunnel kilns, according to the different requirements of users, there are two commonly used schemes: single-point temperature measurement and multi-point switching temperature measurement. They are introduced as follows:
Single-point temperature measurement system: each temperature measurement point is composed of a probe and an instrument box, and the temperature measurement unit is used for temperature collection. Then connect the 4~20MA analog signal output by the instrument box of each unit to the multi-point recorder or the control actuator, and communicate with computers, printers and other equipment through the RS-232 port. La temperatura medida unidad en este sistema generalmente elige HDIR % 7b {5% 7d }A instrumento con alta precisión y fuerte función.
Conmutación temperatura medición sistema: Este sistema es a proceso la señal por conectando el infrarrojo sonda señal instalado at each temperature measurement point to a HDMU-2 multipunto termómetro. Y respectivamente salida 1~5V temperatura señal correspondiente a cada temperatura medida punto para multipunto registrador a grabar. At the same time, the temperature data can be directly input into the computer through the RS232 port, analyzed and processed by the computer, and can also be connected to a printer to print out the temperature data directly .
In the above two schemes, the single-point temperature measurement system has an independent temperature measurement signal processing system for each temperature measurement point, and its output analog and digital signals are real-time continuous signals with fast response speed, which can be used as real-time control signals for controlling the actuators to achieve closed-loop control. However, the multi-point switching temperature measurement system, although the output analog signal is also continuous, has a certain lag with the real-time temperature value, so it can only be used as a data acquisition record, not as a control signal.
In the use of other refractory kilns, such as downdraft kilns and edge kilns, there are fewer temperature measurement points, so more single-point temperature measurement schemes are used.
