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The TR9277-EO is a light harvesting, EnOcean® wireless transmitter, that measures CO2, Temperature and Relative Humidity in an attractive wall mount enclosure. The sensor is powered by ambient indoor light. The CO2 concentration in the space is indicated by pressing a side button and watching the flash sequence of LEDs on the right side of the light-harvesting panel.


Key Features

  • TR9277 uses EnOcean Profile (EEP) A5-09-04 for CO2 Temp and RH.
  • RTH units have options for Temp, Temp+ RH, Temperature Adjust, Occupancy Reset and use corresponding EnOcean EEPs. See datasheet.
  • “Zero Energy” Transmitter that harvests power from ambient light.
  • Integrated CO2 self-calibration feature eliminates maintenance.
  • Built-in absolute pressure sensor corrects CO2 reading for altitude.
  • Utilizes the open, EnOcean® wireless protocol that is designed for integration with other products and systems (ISO/IEC 14543-3-10).
  • Provides feedback on local light strength, and radio signal during installation to facilitate optimum placement.
  • Can be easily calibrated in ambient air to support a seamless commissioning process.
  • Optional battery can be installed to provide extended backup in low light conditions. Five year operation on button battery alone.
  • Smart power management logic manages sampling and message transmission based on real time ambient light levels.
  • Current CO2 level can be read at any time bypressing button and counting LED flashes.

The TR9277-EO is a versatile, wireless CO2, temperature and humidity transmitter that operates based on energy harvested from indoor ambient light. The sensor has no wires and no maintenance and can be installed and integrated into an EnOcean® wireless network in less than a minute. It is specifically designed for smart home and building systems where indoor environmental quality and potential savings from utilizing CO2 based demand controlled ventilation is desired. This sensor platform is ideal for EnOcean® networks installed in new or existing buildings. This product is compatible with most control product gateways designed for the EnOcean® wireless communication protocol