Digital Sensor Module for CO2, Temperature, Humidity and Ambient Pressure The EE894 module is ideal for demand controlled ventilation and building automation. It incorporates the E+E dual wavelength NDIR CO2 sensor, which compensates for ageing effects, is highly insensitive to pollution and offers outstanding long term stability. Beside CO2, the module measures also relative humidity (RH), temperature (T) and ambient pressure (p). A multiple point CO2 and T factory adjustment procedure leads to excellent CO2 measurement accuracy over the entire T working range. The pressure compensation minimizes the impact of altitude and ambient pressure variations onto the CO2 measured data. The measured data, with a range of up to 1% CO2, is available on the I1 2 3C or the E2 digital interface. The EE894 is available in two sizes and with electrical connection via contact pins and pads, which facilitate the design-in. The measured data with a measuring range of up to 1 % CO2 (10 000 ppm) is available on the digital interface PC or E2. An optional kit for the E2 interface facilitates easy configuration of the module and the adjustment of the CO2, RH, T and p measurement. The CO2 measurement interval can be set according to the application requirements; by this the average current consumption can be reduced to 420 jA, ideal for battery-operated devices. Typical Applications_ Demand controlled ventilation Building automation Data loggers and hand helds Wireless transmitters Autocalibration Outstanding long-term stability Temperature and pressure compensated Low power consumption Small size Technical Data_ Measured values Measurement principle Dual wavelength NDIR (non-dispersive infrared technology) Accuracy at 25 °C and 1 013 mbar1) 0...2 000 ppm: < ± (50 ppm +2% of the measured value) Response time t90 105 s with measured data averaging (smooth output) 60 s without measured data averaging2) Temperature dependency, typ ± (1 + CO2 concentration [ppm] / 1 000) ppm/°C (-20...45 °C) (-4...113 °F) Pressure dependency 0.014 % of the measured value / mbar (ref. to 1 013 mbar) Sampling interval from 15 s (factory setup) up to 1 h; user selectable Working range 0...95 %RH (non-condensing) Working range 700.1 100 mbar (10.15...15.95 psi) Temperature dependency ±0.015 mbar/K With data averaging (smooth output) for averaging output. Recommended under normal operating conditions in building automation.

Digital interface Supply voltage Average current 4) at 25 °C (77 °F) and 5 V supply Peak Current I²C or E2 4.75 - 7.5 V DC 420 µA (at 1 h sampling interval) 3.2 mA (at 15 s sampling interval) Current consumption [mA] Warm-up mode Electrical connection Working and storage conditions Measuring mode Sleep mode Contact pins and edge card socket -40...60 °C (-40...140 °F) 0...95 %RH (non-condensing) 700...1 100 mbar (10.15...15.95 psi) 800 ms Sampling interval 15s (configurable up to 1h) 4) The average current depends on the CO2 sampling interval. Connection Diagram / Dimensions in mm (inch) (1.77“)...

Mounting Examples Ordering Guide CO2 + T + RH + p 0...5 000 ppm Standard Contact pads CO2 measuring range: Size: CO2 measuring range: Size: Find Arduino and Raspberry Pi sample codes and more information for easy communication with the EE894 on www.github.com/EplusE. v1.6 / Modification rights reserved