CO₂ Module Measures Four Climate Parameters

EE894
The digital module EE894 measures carbon dioxide (CO₂), relative humidity (RH), temperature (T) and ambient pressure (p). Temperature and pressure compensation ensures high CO₂ measurement accuracy under changing environmental conditions. Very small dimension and the I2C or E2 interface facilitate the design-in.
The dual wavelength NDIR technology with auto-calibration is particularly long-term stable and insensitive to contamination. A multiple point CO₂ and T factory adjustment 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 readings.
The measured data, with a range of up to 1% CO₂, is available on the I²C or the E2 digital interface. Small dimensions and electrical connection via contact pins, edge card socket or pads facilitate the design-in.
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 μA, ideal for battery-operated devices.
Typical Applications
- Demand controlled ventilation
- Building automation
- Data loggers and hand helds
- Wireless transmitters
Key Features
- Dual wavelength NDIR CO₂ working principle
- Measuring range up to 10,000ppm
- Auto-calibration for excellent long term stability
- Temperature and pressure compensation
- High insensitivity to pollution
- Easy user configuration and adjustment
- Very low current consumption
- Miniature size
Technical data
- Measuring range CO₂
- 0...2000 ppm
0...5000 ppm
0...10000 ppm - Accuracy CO₂ at 25 °C (77 °F) and 1013 mbar (14.69 psi)
- ±(50 ppm +2% of mv)
±(50 ppm +3% of mv)
±(100 ppm +5% of mv) - Measuring range Relative Humidity
- 0…95 % RH (non condensing)
- Accuracy Relative Humidity at 25 °C (77 °C) and 20...80% RH
- typ. ± 3 % RH
- Measuring range Pressure
- 700…1100 mbar (10.15...15.95 psi)
- Accuracy Pressure at 25 °C (77 °C) and 20...80% RH
- typ. ± 2 mbar
- Measuring range Temperature
- -40…60 °C (-40...140 °F)
- Accuracy Temperature at 25 °C (77 °F)
- typ. ± 0.5 °C (± 0.9 °F)
- Digital interface
- I²C or E2
- Supply
- 4.75-7.5V DC