JD-3002 Carbon Dioxide Comprehensive Air Quality Temperature Humidity Detector Instrument instructions: 1. After the test, the power of the equipment must be turned off to avoid accidents 2. Prevent the instrument from violent vibration 3. After placing the instrument for a long time, the odor gas will accumulate in the instrument, which will seriously affect the test results, in this case, the instrument must be placed in a cool and ventilated place, and then used for more than 1 hour (no operation is required during the ventilation process instrument) 4. The expired and defective products should be repaired in time. 5. Avoid shocking the sensor with gas higher than the measurement range, otherwise it may damage the sensor, and man-made damage is not covered by the warranty Instrument introduction: 1. Digital temperature and humidity sensor 2. LCD display 3. Mute button: Turn on or off the alarm sound. In the silent mode, the " " symbol is not displayed and there is no alarm sound. The default is to turn on the sound 4. "+" button: When setting the alarm value, increase the value. 5. Power button: long press for 2 seconds to turn on or off the power, when power on, the number field counts down from 120 6. Temperature unit selection button: Celsius and Fahrenheit conversion 7. "-" button: When setting the alarm value, decrease the value 8. Setting button: Short press this button to set the alarm value of "CO2→TVOC→HCHO" in sequence, the original factory setting value will be displayed and flashing, and the parameter will be adjusted by the "+" button and "-" button, and the value will be displayed after 10 seconds. automatic storage 9. Power supply: DC5V built-in 1800mAh lithium battery 10. Dimensions: 195x95x35mm 11. Carton packaging weight: 270 grams Display content introduction: 1. Alarm sound: press the "mute button" to operate 2. CO2 measurement range: 350ppm～2000ppm 3. TVOC measuring range: 0.000 mgm3～2.000 mgm3 4. HCHO measuring range: 0.000 mgm3～1.000 mgm