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Indoor Air Quality (IAQ)

The RW/RLW line of IAQ sensors is designed for air quality measurements in houses, schools, office buildings, restaurants, factory halls and other similar objects. All sensors are placed in a handy white plastic box (IP20 protection) designed for on-wall installation by attaching it into a suitable wiring box (such as KU68).

Four variants in total are offered, featuring sensors of temperature, humidity, light intensity, barometric pressure and VOC (volatile organic compound) concentration. THC models are able to measure CO2 concentration with the indication LED changing its colour from green to red (green = low concentration, red = high concentration). On TH models the LED then serve for the indication of air quality index. The sensors feature measuring of up to six quantities in a single compact package. RLW variants have the same functionality as RW models, but additionally feature the LoRaWAN communication interface. All models are provided with RS485 and Wi-Fi interfaces.

Product datasheets and technical documentation for indoor air quality sensors is available on this link.

Complete overview of individual variants:

The sensors are suitable for usage in offices, schools, commercial buildings, factory halls with internal *LoRa/Wi-Fi networks, but also for household applications. When combined with other technologies the sensors provide the option to maintain stable air quality, creating a comfortable environment for work or relaxation.

*LoRaWAN is available only for RLW-TH and RLW-THC variants

For more information about possible applications of Unipi IAQ sensors with LoRa interface, visit Integration of an IoT indoor air quality sensor with LoRa communication case study.

RW-TH

  • the most basic IAQ variant
  • features sensors for measuring temperature, relative air humidity, light intensity, barometric pressure and VOC concentration
  • LED indication of air quality index
  • does not contain CO2 sensor and LoRaWAN interface

Examples of use:

  • measuring temperature and relative air humidity to provide data for HVAC regulation
  • using internal air quality data for regulation of ventilation and air recovery
  • controlling indoor artificial lights according to ambient light levels

Possible applications:

  • when used with Unipi PLCs: an element of MaR systems using the Modbus RTU/TCP protocol
  • usage within a third-party system through RS485 or Wi-Fi interface using a suitable communication protocol
  • individual use - communication through Wi-Fi with the option of web server access

RW-THC

  • integrated CO2 sensor and a LED indication of CO2 concentration
  • features sensors for measuring temperature, relative air humidity, light intensity, barometric pressure, VOC concentration and CO2 concentration
  • does not contain the LoRaWAN interface

Examples of use:

  • measuring temperature and relative air humidity to provide data for HVAC regulation
  • using internal air quality data (enhanced by CO2 concentration measurements) for regulation of ventilation and air recovery
  • controlling indoor artificial lights according to ambient light levels

Possible applications:

  • when used with Unipi PLCs: an element of MaR systems using the Modbus RTU/TCP protocol
  • usage within a third-party system through RS485 or Wi-Fi interface using a suitable communication protocol
  • individual use - communication through Wi-Fi with the option of web server access

RLW-TH

  • variant featuring LoRaWAN interface
  • features sensors for measuring temperature, relative air humidity, light intensity, barometric pressure and VOC concentration
  • LED indication of air quality index
  • does not contain CO2 sensor and LoRaWAN interface

Examples of use:

  • measuring temperature and relative air humidity to provide data for HVAC regulation
  • using internal air quality data for regulation of ventilation and air recovery
  • controlling indoor artificial lights according to ambient light levels

Possible applications:

  • when used with Unipi PLCs: an element of MaR systems using the Modbus RTU/TCP protocol
  • usage within a third-party system through RS485 or Wi-Fi interface using a suitable communication protocol
  • individual use - communication through Wi-Fi with the option of web server access
  • individual use - communication via LoRaWAN (up to 16 bytes of transmitted data, containing up to 10 values, with a user-configured interval (limited by the relevant legislation and/or service fees)

RLW-THC

  • variant featuring the LoRaWAN interface
  • integrated CO2 sensor and a LED indication of CO2 concentration
  • features sensors for measuring temperature, relative air humidity, light intensity, barometric pressure, VOC concentration and CO2 concentration

Examples of use:

  • monitoring of internal air quality (enhanced by CO2 concentration measurements) to provide data from controlling air recovery or ventilation control
  • measuring temperature and relative air humidity to control HVAC systems
  • controlling indoor lights according to the ambient light intensity

Possible applications:

  • when used with Unipi PLCs: an element of MaR systems using the Modbus RTU/TCP protocol
  • usage within a third-party system through RS485 or Wi-Fi interface using a suitable communication protocol
  • individual use - communication through Wi-Fi with the option of web server access
  • individual use - communication via LoRaWAN (up to 16 bytes of transmitted data, containing up to 10 values, with a user-configured interval (limited by the relevant legislation and/or service fees)

Example of binary payload decoder. Function names are in accordance with The Things Network.

function getBit(number, bitPosition) {
  return (number & (1 << bitPosition)) === 0 ? 0 : 1;
}
function Decoder(bytes, port) {
  // Decode an uplink message from a buffer
  // (array) of bytes to an object of fields.
  var decoded = {};
  if (getBit(bytes[0],0)) {
    decoded.temperature = ((bytes[2] << 8) | bytes[1]) / 100 - 100;
    decoded.relative_humidity = bytes[3] / 2.5;
  }
  if (getBit(bytes[0],1)) decoded.pressure = ((bytes[5] << 8) | bytes[4]) / 100 + 800;
  if (getBit(bytes[0],2)) {
    decoded.voc_index = ((bytes[7] << 8) | bytes[6]) & 0x01FF;
    decoded.voc_accuracy = ((bytes[7] << 8) | bytes[6]) >> 9 & 0x0003;
  }
  if (getBit(bytes[0],3)) decoded.ambient_light = Math.exp(bytes[8] / 20) - 1;
  if (getBit(bytes[0],4)) decoded.co2 = ((bytes[10] << 8) | bytes[9]);
  if (getBit(bytes[0],5)) {
    decoded.pm10 = (((bytes[13] << 16) | (bytes[12] << 8) | bytes[11]) >> 12) & 0x000FFF / 4;
    decoded.pm2_5 = ((bytes[13] << 16) | (bytes[12] << 8) | bytes[11]) & 0x000FFF / 4;
  }
  if (getBit(bytes[0],6)) {
    decoded.noise_duration = (bytes[14] / 2);
    decoded.noise_intensity = (bytes[15] / 5) + 25;
  }
  return decoded;
}