DHM2 ventilation dry wet bulb thermometer wholesale

DHM2 mechanical ventilation dry wet gauge dry wet bulb thermometerBasic Parameters:
1. Working temperature: It can work normally in an environment of -10 ℃ to 45 ℃ when measuring air humidity.
2. Humidity measurement range: 10% RH to 100% RH
3. Scale range of thermometer: -26 ℃ to+51 ℃
4. Small division value of thermometer scale: 0.2 ℃
5. Ventilation speed: ≥ 2.5m/s
6. Instrument weight: 2.5kg (complete set of instruments)
7. Dimensions: Aluminum alloy outer box 135mm × 160mm × 450mm
8. Standard level: Meets the second-class standards for temperature instruments and humidity instruments
DHM2 mechanical ventilation dry wet gauge dry wet bulb thermometerWorking Principle:
Also known as the Asman dry wet bulb hygrometer, the working principle is to fully wind the wind of the ventilator, causing the fan to rotate and give a certain speed of air flow, flowing through two parallel thermometers, one of which has a mercury bulb wrapped with soaked degreased gauze. Due to the evaporation of moisture on the gauze, the temperature of the thermometer decreases. By comparing the temperature difference between two thermometers (wet and not wet), the relative humidity and humidity of the air can be calculated through table conversion. Longtuo Hand cranked Wet and Dry Meter, Longtuo Electric Ventilation Wet and Dry Meter, and Longtuo Mechanical Ventilation Wet and Dry Meter are professionally supplied by Longtuo Instruments in Shanghai.
Basic characteristics of Asman dry wet bulb hygrometer:
1. The Fengyun brand dry wet bulb thermometer has a fully metal structure, compact and beautiful appearance, strong craftsmanship, and accurate readings.
2. The scale range of the thermometer is -26 ℃ to+51 ℃; Small division value: 0.2 ℃, accurate indication.
3. The measured value * conforms to the data designed in the "Meteorological Common Table No. 2".
4. The ventilation part is driven by spring springs and does not require a power source, making it more suitable for outdoor and mining use without a power source.
5. Shanghai Longtuo supplies ventilation hygrometers suitable for measuring air temperature and relative humidity in large, medium, and small meteorological stations, weather stations, environmental monitoring stations, industrial and mining enterprises, laboratories, museums, etc. They can also be used as second-class standard instruments to verify other temperature and humidity equipment.
Operation steps of mechanical ventilation dry wet meter:

When using a ventilation psychrometer, it should be hung before observation. The place where the ventilation psychrometer is hung should ensure that the obstacles around the instrument are at least 0.5 meters away from the bulb of the thermometer. This is to avoid the thermal radiation of the obstacles themselves affecting the measurement value of the thermometer. The operator should stay at least 0.5 meters away and approach it before reading: After the ventilation psychrometer is hung, it must be observed after a certain period of time (at least 15 minutes in summer and at least 30 minutes in winter).
Before observation, the gauze cover of the wet bulb thermometer should be moistened. The time for moistening the gauze cover is 4 minutes before observation in summer and 15 minutes before observation in winter (if it is frozen, it should be melted). Wetting is the standard, and there should be no dripping before observation. The moistening gauze cover should be made using the instrument's accessory glass water tube, rubber bag, and clip. Distilled water and rainwater should be used for moistening the gauze cover, and well water, spring water, or tap water should not be used. Each observation needs to be re moistened. The instrument must not be inverted when adding water. After wetting the gauze cover, tighten the winding of the ventilator. To prevent the fan from rotating, gently insert a paper rod from the exhaust hole before winding to stop the fan. When working, remove the paper rod (which can be made of thick paper or multiple layers of thin paper: hard or metal objects are prohibited), wait for the ventilator to rotate for 4 minutes, and then read the temperature gauge. When reading, the eyes should be level with the top of the mercury column. First read the decimal, then read the integer, and correct the reading (that is, compare it with the standard temperature gauge listed in the calibration certificate of the two temperature gauges to obtain the correction value at each point of 10 ° C on the gauge, and correct it to eliminate errors). Then, based on the corrected dry bulb temperature and wet bulb temperature, the air humidity value or relative value can be calculated in the commonly used meteorological gauge (this instrument comes with a simple temperature lookup table).
When taking readings, the operator should stand in the downwind direction and read quickly and accurately.After the measurement is completed, the instrument can only be retracted after the fan blades of the instrument have stopped rotating. When used in the wild, if the wind speed is greater than 3M/S, a windshield should be installed on the windward side of the ventilation dry wet meter ventilator. To prevent adverse effects beyond ventilation speed.