Description
Measuring instruments in green houses or life stock barns are exposed to a very demanding environment: high humidity levels, pollutants like fertilizers, herbicides and high ammonia concentrations are just a few of the many hazards. The robust, functional housing of the EE82 with integrated special filter has been designed for such applications. The air diffuses through the filter into the instrument enclosure. Then the air diffuses further through a second membrane filter integrated in the CO2 measuring cell. The CO2 measurement is based on the non-dispersive infrared (NDIR) technology. The patented auto-calibration procedure compensates for aging of the infrared source and guarantees high reliability, long term stability and eliminates the need of periodical recalibration in the field. Measuring ranges of 0…2000/5000/10000ppm correspond to an analogue interface of 0 – 5/10V or 4 – 20mA. Selectively a switching output with adjustable switching point and hysteresis is available.
- Measuring principle: Non-Dispersive Infrared Technology (NDIR)
- Measuring range: 0 to 2000 / 5000 / 10000ppm
- Accuracy at 25°C and 1013mbar: 0 to 2000ppm: < ± (50ppm +2% of measuring value), 0 to 5000ppm: < ± (50ppm +3% of measuring value), 0 to 10000ppm: < ± (100ppm +5% of measuring value)
- Response time: τ63 < 195s
- Temperature dependence: typ. 2ppm CO2/°C
- Long term stability: typ. 20ppm / year
- Sample rate: approx. 15s
- Analogue Output: 0 to 2000 / 5000 / 10000ppm 0 – 5 / 0 – 10V, 4 – 20mA RL < 500 Ohm
- Switching Output: Max. switching voltage 50V AC / 60V D, Max. switching load 0.7A at 50V AC 1A at 24V DC, Min. switching load 1mA at 5V DC, Contact material Ag+Au clad
- Supply voltage 24V AC ±20% 15 – 35V DC
