EE850 Flansch frei oH large

Technical Inquiries

support-form3

Carbon Dioxide Transmitters

Carbon dioxide (CO2) is a gaseous component of the earth's atmosphere. The concentration of CO2 in natural ambient air is about 0.04% or 400ppm. With each breath, humans convert oxygen (O2) into carbon dioxide. Although carbon dioxide is invisible and odorless, an increased CO2-content is apparent because humans will notice increased fatigue and reduced concentration. In rooms with high occupancy such as conference rooms and theatres, negative effects become all the more evident. Modern climate control can assure optimal air quality by adjusting the supply of fresh air based on the measurement of CO2 concentration in the indoor air. The CO2-concentration is regarded as an important measure of indoor air quality.

CO2 measurements in HVAC applications are based exclusively on the Infrared (IR) absorption principle. There are two methods to measure CO2 concentration with the IR absorption method: Non-Dispersive Infrared (NDIR) absorption sensor and Photo-Acoustic sensor.

Compared with the photo-acoustic sensors, NDIR absorption sensors offer the following advantages: less sensitive to pressure variations, vibrations and acoustic interference. In addition, carbon dioxide transmitters are more compact.

A patented auto-calibration procedure uses two IR-sources with distinct operation cycles: one IR-source operates to measure the CO2 concentration and generates an IR signal every 30 seconds. The second IR-source, the reference source, is used for the auto-calibration only. This source is activated twice every 24 hours, which leads to virtually no aging and therefore to negligible drift. The quasi drift-free signal of the reference source is used to offset eventual drifts of the measuring source.

The advantages of this two-source-two-beam measuring principle for carbon dioxide transmitters are obvious, easy drift compensation with stable IR-reference source and the use of a one simple IR-filter (other methods use two IR-filters or complicated switchable IR-filters), and only one detector required.

The carbon dioxide transmitters are offered in different packages. The EE80 for wall mounting in rooms and other spaces visited by humans, e.g. museums and conference rooms. The EE820 is specifically design for harsh, demanding applications, like stables, green and ware houses, hatchers and incubators, fruit and vegetable storage. For typical HVAC application the duct mounted EE850 transmitter will be the preferred instrument. The available ranges are 0 – 2000 / 5000 / 10000 ppm carbon dioxide.

In places where people gather and the carbon dioxide level is measured and controlled, the need for humidity transmitters to measure the humidity and temperature is almost imperative to ensure a comfortable work environment.

 

CO2 Transmitters for Room, incl. T and / or %RH
Series EE80
CO2 Transmitters for Room

 

  • Carbon Dioxide Range: 0 - 2000 ppm / 0 - 5000 ppm
  • Accuracy co2: < ± (50 ppm + 2% of reading) for 0 - 2000 ppm
                            < ± (50 ppm + 3% of reading) for 0 - 5000 ppm
  • %RH range: 10 - 90 %RH
  • Temperature range: 23 - 131 °F (-5 - 55 °C)
  • Outputs: 0 - 5 Vdc, 0 - 10 Vdc or 4 - 20 mA; relay 50 Vac / 60 Vdc
  • Model - CT for co2 and Temperature - active
  • Model - CP for co2 and Temperature - passive
  • Model - CTF for co2, Temperature and Relative Humidity
  • Model - C-S for co2 and relay output only!
  • US-version; will fit electrical outlet box
  • Auto calibrate
  • Optional display

CO2 Transmitter for Agriculture Applications
Series EE820
EE820 DB small

 

  • Dual wavelength non-dispersive infrared technology (NDIR)
  • Carbon Dioxide Range: 0 - 2000 ppm / 0 - 5000 ppm / 0 - 10000 ppm
  • Accuracy: < ± (50 ppm + 2% of reading) 0 - 2000 ppm
                     < ± (50 ppm + 3% of reading) 0 - 5000 ppm
                     < ± (100 ppm + 5% of reading) 0 - 10000 ppm
  • Outputs: 0 - 5 V / 0 - 10 V / 4 - 20 mA
  • Supply voltage: 24 Vac ± 20% / 15 - 35 Vdc
  • Auto calibration / Long-term stability
  • High resistance to pollution
  • Enclosure Polycarbonate - IP65 / NEMA 4X
  • Plug connection optional

 

 CO2 Transmitter for Duct Mounting
Series EE850
 EE850 Flansch frei oH small

 

  • Dual wavelength non-dispersive infrared technology (NDIR)
  • Carbon Dioxide Range: 0 - 2000 ppm / 0 - 5000 ppm / 0 - 10000 ppm
  • Accuracy: < ± (50 ppm + 2% of reading) for 0 - 2000 ppm
                     < ± (50 ppm + 3% of reading) for 0 - 5000 ppm
                     < ± (100 ppm + 5% of reading) for 0 - 10000 ppm
  • Outputs: 0 - 5 Vdc / 0 - 10 Vdc / 4 - 20mA
  • Passive Temperature output optional
  • Supply voltage: 24 Vac ± 20% / 15 - 35 Vdc
  • Auto calibration
  • Enclosure Polycarbonate - IP65 / NEMA 4X; probe IP20

 

 CO2 Probes for OEM / HVAC Applications
Series EE870 / EE871
 
CO2 Probe

 

  • Carbon Dioxide Range: 0 - 2000 ppm / 0 - 5000 ppm / 0 - 10000 ppm
  • Accuracy: < ± (50 ppm + 2% of reading) 0 - 2000 ppm
                     < ± (50 ppm + 3% of reading) 0 - 5000 ppm
                     < ± (100 ppm + 5% of reading) 0 - 10000 ppm
  • Digital output E2 (2-wire) probe EE871
  • Supply voltage EE871: 4.75 - 7.5 Vdc
  • Conversion board EE870: 10 -135 Vdc / 10 - 28.8 Vac
  • Analogue outputs EE870: 0 -1 /5 /10 V and 0 (4) - 20 mA
  • Extreme low power consumption
  • Auto calibration

 

CO2 Module for OEM / HVAC Applications
Series EE893
EE893 small 

 

  • Carbon Dioxide Range: 0 - 2000 ppm / 0 - 5000 ppm / 0 - 10000 ppm
  • Accuracy: < ± (50 ppm + 2% of reading) 0 - 2000 ppm
                     < ± (50 ppm + 3% of reading) 0 - 5000 ppm
                     < ± (100 ppm + 5% of reading) 0 - 10000 ppm
  • Digital output E2 (2-wire)
  • Supply voltage: 4.75 - 7.5 Vdc
  • Extreme low power consumption
  • Auto calibrate

 

Please note: Manual data files can be quite large, please be patient while downloading.
The manuals are for information purposes only and shouldn't be used for operating the instrument