IRC-A1 CARBON DIOXIDE INFRARED SENSOR PYROELECTRIC DETECTOR Technical Specification Figure 1 NDIR-A Schematic Diagram Top View Pin out details: 1. Lamp return 2. Lamp +5V 3. +5V Pyro supply 4. Detector output 5. Reference output 6. Thermistor output 7. OV Pyro supply and case connection Bottom View Side View Notes: 1. Dimensions without tolerances are nominal 2. Recommended PCB socket: Wearnes Cambion Ltd. code: 450-3326-01-06-00 3. Weight: 15g 4. Use antistatic precautions when handling 5. Do not cut pins 6. Do not solder directly to pins PERFORMANCE Maximum Power Requirements Minimum Operating Voltage Source Drive Frequency Active Output in N2 (peak-to-peak) Reference Output in N2 (peak-to-peak) Response Time (t90) Warm-up Time 5.0 VDC, 60mA max. (50% duty cycle source drive) 2.0 VDC, 20mA max. (50% duty cycle source drive) 1.5 to 3 Hz (recommended 2 to 2.25 Hz) 60 - 100mV @ 2.1 Hz, 50% duty cycle 40 - 80mV @ 2.1 Hz, 50% duty cycle < 40s @ 20°C ambient To final zero ± 100ppm: < 30 s @ 20°C To specification: < 30 minutes @ 20°C LIFETIME MTBF KEY SPECIFICATIONS Temperature Signal Operating Temperature Range Storage Temperature Range Humidity Range Integral thermistor (NTC, R25 = 3000 Ω Β= 3450 K) -20°C to +50°C (linear compensation from -10 to 40°C) -40°C to +75°C 0 to 95% rh non-condensing Range (Application) Accuracy (%FS, using universal linearisation coefficients) Zero Resolution Full Scale Resolution Zero Repeatability Full Scale Repeatability * When ordering, select ‘IAQ’ or ‘Other’, depending on your application. NOTE: all sensors are tested at ambient environmental conditions, unless otherwise stated. As applications of use are outside our control, the information provided is given without legal responsibility. Customers should test under their own conditions, to ensure that the sensors are suitable for their own requirements. Alphasense Ltd, Sensor Technology House, 300 Avenue West, Skyline 120, Great Notley. CM77 7AA. UK Telephone: +44 (0) 1376 556 700 Fax: +44 (0) 1376 335 899 E-mail: [email protected] Website: www.alphasense.com

IRC-A1 Perf erformance Data IRC-A1 Performance Data Absorbance of change (zeroed at 02:00) Comparison of resolution of IRC-A1 (red) and competitor’s 20mm diameter NDIR cell (blue). Both cells were operated at 2.25 Hz with the same electronic circuit. Both cells use the same light source and dual pyroelectric detector. The improved resolution of the IRC-A1 is due to the patent pending optical design. Figure 3 Beer-Lambert Performance 0.25 Typical response from 0 to 5000ppm CO2. Experimental Data Curve Fit (Standardised Coefficients) Curve Fit (Beer's Law) The fit is very close to the theoretical...

IRC-A1 Perf erformance Data IRC-A1 Performance Data Figure 5 Linearisation Custom linearisation is not necessary with the IRC-A1. Using universal linearisation constants, repeatability between cells is very good, allowing easy implementation. For an IAQ application, a zero and then single calibration at 4,000ppm CO2 gives the error shown above: less than 2% of reading and typically less than 0.5% of reading for six different IRC-A1 cells. Excellent stability and resolution at 1000ppm CO2 for the IRC-A1 is achieved by better design, not by using more expensive components. Technical Specification...