Due to the fact that CO2 is an important indicator for the quality of air in rooms, it's superimportant to measure the CO2 content. The recommended CO2 limit value for ambient air is 1000ppm. An exceeding of this limit causes tiredness and a loss of concentration.
For measuring the CO2 concentration, GREISINGER electronics presents a high quality and precise CO2 transmitter, working according to the infrared principle (NDIR). An auto-calibration procedure compensates for aging effects and is responsible for an excellent long term stability of this CO2 transducer. Due to the freely adjustable output signal (4-20mA, 0-1V. 0-10V etc.), the transmitter could be used for nearly each existing controller input etc .. Additionally, there is a local display which shows beside the actual CO2 concentration, the minimum and maximum values ​​as well as an optical alarm. If required, the CO2 transmitter could be calibrated via buttons.
Highlights:
excellent long term stability
auto-calibration procedure
for surveillance of the recommended CO2 concentration in ambient air
local display
output signal freely adjustable
zero point and scale input
visual alarm display
Technical Details:
Measuring Range: 0 ... 2000 ppm CO2
Accuracy: ± 50 ppm ± 2% of reading (at 20 ° C, 1013mbar) 
Output Signal: 4-20mA (optional 0-1V, 0-10V etc.), freely adjustable
Connection Type: 4-20 mA (3-wire system)
Power Supply: Uv = 12 - 30 V DC, Max. 500mA 
Calibration: zero and scale via button adjustable
Display: approx. 10 mm high, 4-digit LCD display
Housing: ABS (IP65)
Dimensions: 82 x 80 x 55 mm (without angle plug)
Features: minimum / maximum value memory, optical alarm
                                          input of zero and scale