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Temperature transmitter, temperature humidity transducer, co transducer,co2 transducer, air velocity transmitter. LEFOO has various transmitters that have LCD digital readings, easy to install, have a long service life
  • Temperature And Humidity Sensor +
    Temperature And Humidity Sensor

    Temp and humidity sensor
    Anti-interference: Response Time 10S
    Measure Range: 0%~100%RH
    Measure Precisement: 2% F.S
    LCD backlight: Temperature + Relative Humidity

  • Temperature Transmitter +
    Temperature Transmitter

    Lefoo Temperature Transducer
    Various Outputs and Mountings
    Apply Heraeus A-class Sensor
    Protection Level IP65+ Anti-interference
    CE& RoHS certificated

  • Electrochemical CO Transducer +
    Electrochemical CO Transducer

    Electrochemical CO sensor
    Long Serve life: Over 5 years
    Working Tmperature:-10~50°C
    Measuring Density: 0~550ppm / 0-1000ppm
    Outputs: 4-20ma / 0-5V / 0-10V / RS485

  • CO2 Detector Carbon Dioxide Monitor +
    CO2 Detector Carbon Dioxide Monitor

    Carbon Dioxide Sensor
    Protecting Level: IP6X
    Serve Life: Over 5 years
    Measure Accuracy:(40PPM±3%FS)
    Measure Density:0-2000~5000~10000PPM

  • Residual Pressure Sensor +
    Residual Pressure Sensor

    Sensor for Residual Pressure Measurement
    Pressure range: ±100 pa
    Pressure Accuracy: ±1% FSO
    Application: HVAC System, Fire Prevention
    Indicator color: Green for Normal Red for Alarm

  • Air Velocity Transmitter +
    Air Velocity Transmitter

    AirSpeed and Wind Speed Transmitter Undergo the final tests and will come soon

Each environment transmitter (analyzer) has internal or external sensors that connect a variety of digital probes and give out signals such as 4-20 mA,0-5V,0-10V, RS485, the customize signal level are also available, which provide a convenient range of signal types. The transmitter can mount discretely to the wall in the library, museums, supermarkets, computer server chambers, workshops, warehouses, and any facility requiring environmental monitoring. The environment transmitter may be powered from a DC adapter to operate on any voltage worldwide from 12V dc to 240 V dc

Temperature and Humidity Sensor

There is a temperature-sensitive resistance and a humidity-sensitive resistance in the probe of the temperature and humidity sensor, the resistant value can be proportional or inversely proportional to temperature, the humidity resistance will absorb moisture from the ambient air, Proportional or inversely proportional to temperature.  The temperature and humidity sensor is applied in HVAC, Server centers, Heat treating, Environmental testing, ship or airplane, Meteorological Pharmaceutical, Food industries, Animal husbandry, Power generation, Nuclear power plant safety, Wood related industry, Wine and beverage...

CO2 transmitter

The CO2 transmitter is based on the Non-Dispersive Infrared (NDIR) theory. When the IR light passes through the length of the tube, the CO2 gas molecules absorb the specific band of IR light while letting other wavelengths of light pass through. At the detector end, the remaining light hits an optical filter that absorbs every wavelength of light except the wavelength absorbed by CO2 molecules in the air sample tube.

Finally, an IR detector reads the remaining amount of light that was not absorbed by the CO2 molecules or the optical filter.

How is the CO2 level calculated?

The difference between the amount of light radiated by the IR lamp and the amount of IR light received by the detector is measured. Since the difference is the result of the light being absorbed by the CO2 molecules in the air inside the tube, it is directly proportional to the number of CO2 molecules in the air sample tube.

All measurements start out as analog micro-voltages. While some sensors output this as an analog voltage or 4-20mA signal, some also include an analog to digital converter on the sensor PCB that converts the voltages into serial or RS-485 output.

Residual Pressure Transmitter

Residual pressure monitoring is a low differential pressure-based measurement. Residual pressure transmitters are used in applications such as pressure detection of fire passage.

CO Transmitter

The CO transmitter is based on electrical-chemistry theory, When carbon monoxide is converted to oxygen, carbon monoxide loses electrons and oxygen obtains electrons. This process will generate a weak nano ampere level current, which is then through RGF signal amplifier transduced to milliampere level through. The current value is proportional to the concentration of carbon monoxide.

We had glanced the great advance in automation technology among industry, transportation, medical treatment, store and restaurant management lab research, business campus, and public buildings in the last century and last decade. Hense, LEFOO had the mission to produce environmental transmitters (or analyzers) to assure the measurement for environmental monitoring applications. Such as temperature and humidity sensor, residual pressure transmitter, air velocity transmitter, co transmitter,co2 transmitter. The whole product requiring very low power consumption and can easily be mounted virtually on the wall.