1, the first thing is to press and hold the red button in the middle of the button. Note that it takes 10 seconds. At this time, the infrared thermometer will automatically restore the factory settings.

2. Next, set and calibrate, and then turn to one side of the infrared thermometer. At this time, notice that there is a groove here, as shown in the figure below.

3, and then you need to push hard to the right by hand or screwdriver to open it.

Then, when you open it, you can see that there is a temperature selection switch on the battery box. The default location is℃ (Celsius).

5. Then, you need to turn the switch to the "⊙" position, that is, set the temperature display unit to Fahrenheit.

6. After closing the battery cover, you can see that the display screen has been switched to Fahrenheit, and the calibration is complete.

Factors affecting the inaccuracy of infrared thermometer measurement

Firstly, the relationship between the size of the temperature measurement target and the temperature measurement distance.

According to the principle, in vitro thermometers can be divided into monochromatic thermometers and bicolor thermometers (radiation colorimetric thermometers). For a monochromatic thermometer, when measuring the temperature, the target area to be measured should fill the field of view of the thermometer. It is suggested that the size of the measured object should exceed 50% of the field of view. If the target size is smaller than the field of view, the background radiation energy will enter the visual symbol branch of the thermometer, which will interfere with the temperature measurement reading and cause errors.

Secondly, the emissivity of the measured substance is selected.

Generally, infrared thermometers are classified by blackbody (emissivity ε= 1.00), but in fact, the emissivity of materials 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 a substance can be found in the emissivity data of an object in radiation thermometry.