E+E Elektronik has added an additional passive temperature measurement function to the tried-and-tested EE85 CO2transmitter for precise measurement of CO2 concentrations and temperatures in HVAC applications. CO2and temperature measurement in a single device cuts installation costs for sensors.
The combined CO2 temperature transmitter is ideally suited for applications in the fields of building management and demand controlled ventilation. The elegant, compact housing enables easy installation directly at the ventilation duct using a mounting flange.
The CO2 measurement of the EE85 is carried out using infrared technology (NDIR). The patented auto-calibrate function compensates for any ageing effects (even if there is no fresh air supply) and ensures excellent long-term stability. The air to be monitored is conveyed to the measurement cell in the housing by means of convection via the measuring head and a 12-mm pipe. The exchange of gas with the measurement cell is performed by diffusion via a diaphragm. In this way, the gas in the measurement cell circulates in a closed system. This prevents any soiling of the optical measurement path and any associated inaccuracies in the measurements.
The temperature the sensor is installed directly in the tip of the measurement sensor and optimally protected against soiling by a diaphragm filter. The passive temperature sensor signal is available at the connection terminals in the housing and can be connected directly to the majority of control devices.
The measuring ranges 0 – 2.000 / 5.000 / 10.000 ppm are available. The temperature range is -20…60°C.
Since a CO2 concentration of room air above 1.000 ppm affects our performance, it is important to measure the CO2concentration in addition to the standard climatic conditions for rooms (such as temperature and relative humidity). In this way, it is possible to take early and cost-effective actions to remedy poor air quality (for example, by increasing the fresh air supply as required).