Available here is a Drager Polytron IR CO2 Carbon Monoxide Gas Detector. This came from the surplus of a large company. It looks to me like it is new but I don't know for sure. I don't have a power supply to test this with but I will guarantee it to function properly when you receive it. Just try it out within 7 days of receiving it and if it doesn't work right you can send it back for a full refund. The part number on this unit is 8312576.
The Dräger Dräger Polytron IR CO2 is a gas detector for continuous monitoring of carbon dioxide in ambient air. The measuring range can be adjusted from 0-2000 ppm up to 30 Vol%.
The transmitter uses state-of-the-art microprocessor technology to convert the signal from an infrared DrägerSensor to a 4 to 20 mA analog signal output.
The unit is designed for one-man calibration, and offers a variety of diagnostics and self test features. The configuration and calibration of the transmitter is menu guided and easy to perform, using the built-in push buttons.
Type Transmitter with infrared sensor technology
Measuring range (full scale value) Configurable between 2000 and 9990 ppm, or between 1 and 30 % by vol.
Power supply 13 to 30 V DC (nominal 24 V DC), < 2 W
Output signals Operation: 4 to 20 mA
Maintenance signal: 2 / 5 mA, 1 Hz modulation, or 3 mA constant, configurable
Warning signal: 2 / 5 mA, 1 Hz modulation, or 2 mA every 10 s,
or 2 mA constant, configurable
Fault signal: < 3 mA or 1 mA, configurable
Measuring line 3-core, shielded, core cross section 0.5 to 1.5 mm2, outer diameter 6 to 12 mm
Maximum cable length (at 24 V) 2000 m for 3 x 1.5 mm2; 1500 m for 3 x 1.0 mm2; 1000 m for 3 x 0.75 mm2
Response time (at 25 °C / 77 °F) t
Ambient conditions Temperature - 20 to + 65 °C / - 4 to + 150 °F (- 40 °C / - 40 °F on request)
Pressure 700 to 1300 hPa / 23.6 to 32.5 inch Hg
Enclosure IP 65, glass fibre reinforced polyester (GRP)
Size 140 x 160 x 90 mm / 5.6 “ x 6.4 “ x 3.6 “ (w x h x d, incl. sensor and cable gland)
Weight ca. 1.9 kg, remote display unit: 1.0 kg
Approvals Ex-approved version II 2G EEx me [ib] d IIB+H
a ? + 65 °C (- 40 °F ? Ta ? + 150 °F)
CE-marking Electromagnetic compatibility (directive 89/336/EEC)
