WIKA A2G-85 - Manual (Page 10)

WIKA operating instructions air2guide model A2G-85
GB
10
40339564.02 07/2012 GB/D/F/E/I
6. Commissioning, operation
Connection cable 1.5 m
Electrical connection
When using long connection cables, and depending on the cross-
section used, the measuring result might be falsified due to a voltage
drop on the common GND line, caused by the supply current and the
line resistance. In this case 2 GND lines must be laid to the CO
2
sensor
- one for the supply current and one for the measuring current.
Classes for the indoor air quality (EN 13779)
brown Supply voltage +24 V
white Reference potential GND
yellow Output measured value CO
2
Category CO
2
content above the content
in the ambient air in ppm
Description
Typical range Standard value
IDA1 < 400 ppm 350 ppm High indoor air quality
IDA2 400 ... 600 ppm 500 ppm Mean indoor air quality
IDA3 600 ... 1,000 ppm 800 ppm Moderate indoor air quality
IDA4 > 1,000 ppm 1,200 ppm Low indoor air quality
Measuring principle
For the CO
2
measurement the "Non Dispersive InfraRed (NDIR)"
technology with automatic self-calibration (ABCLogic™) is used. For