Measuring Principle - WIKA A2G-85 Manual De Instrucciones

6. Commissioning, operation
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
GB
line resistance. In this case 2 GND lines must be laid to the CO
- one for the supply current and one for the measuring current.
Classes for the indoor air quality (EN 13779)
Category
IDA1
IDA2
IDA3
IDA4

Measuring principle

For the CO
2
technology with automatic self-calibration (ABCLogic™) is used. For
10
Connection cable 1.5 m
CO content above the content
2
in the ambient air in ppm
Typical range
< 400 ppm
400 ... 600 ppm
600 ... 1,000 ppm
> 1,000 ppm
measurement the "Non Dispersive InfraRed (NDIR)"
WIKA operating instructions air2guide model A2G-85
brown Supply voltage +24 V
white Reference potential GND
yellow Output measured value CO
Standard value
350 ppm
500 ppm
800 ppm
1,200 ppm
2
2
Description
High indoor air quality
Mean indoor air quality
Moderate indoor air quality
Low indoor air quality
sensor