Factors Having an Impact on FIR Thermometers
1. The relationship between the temperature measurement target size and the temperature measurement distance: at different distances, the effective diameter D of the measurable target is different, so pay attention to the target distance when measuring small targets. The definition of the distance coefficient K of the infrared thermometer is: the ratio of the distance L of the measured target to the diameter D of the measured target, that is, K=L/D
2. Select the emissivity of the substance to be measured: Infrared thermometers are generally graded according to black bodies (emissivity ε=1.00), but in fact, the emissivity of the substance is less than 1.00. Therefore, when the real temperature of the target needs to be measured, the emissivity value must be set. The emissivity of matter can be found from "Data on emissivity of objects in radiation thermometry".
3. Measurement of targets in a strong light background: If the measured target has a brighter background light (especially under direct sunlight or strong lights), the accuracy of the measurement will be affected, so objects can be used to block the direct light of the target to Eliminate background light interference.
4. Measurement of small targets
⑴The thermometer should be fixed on the tripod (optional accessory)
⑵Accurate focusing is required, that is: use the small black dots in the eyepiece to aim at the target (the target should be full of small black dots), adjust the lens back and forth, and shake your eyes slightly. If there is no relative movement between the measured small black dots, adjust coke is done
5. Temperature output function
(1) Digital signal output - RS232, RS485, temperature signal remote transmission
(2) Analog signal output - 0~5V, 1~5V, 0~10V, 0/4~20mA, which can be added to the closed-loop control.
(3) High alarm, low alarm - In the production process, it is required to control the temperature within a certain range, and the high and low alarm values can be set. High alarm: When the high alarm setting is turned on, when the temperature is higher than the high alarm value, the corresponding LED light will flash, the buzzer will sound, and the AH normally open relay will be connected.
Features of Far Infrared Thermometer
1. Non-contact measurement: It does not need to touch the inside or surface of the measured temperature field, so it will not interfere with the state of the measured temperature field, and the thermometer itself will not be damaged by the temperature field.
2. Wide measurement range: Because it is a non-contact temperature measurement, the thermometer is not in a higher or lower temperature field, but works at a normal temperature or under the conditions allowed by the thermometer. Under normal circumstances, it can measure minus tens of degrees to more than three thousand degrees.
3. Fast temperature measurement speed: that is, fast response time. As long as the infrared radiation of the target is received, the temperature can be fixed in a short time.
4. High accuracy: Infrared temperature measurement will not destroy the temperature distribution of the object itself like contact temperature measurement, so the measurement accuracy is high.
5. High sensitivity: As long as there is a small change in the temperature of the object, the radiation energy will change greatly, which is easy to detect. The temperature measurement of the tiny temperature field can be carried out.
6. Temperature distribution measurement, and temperature measurement of moving or rotating objects. It is safe to use and has a long service life.
