ROTRONIC CF8-D/W-IN User Manual
Page 5
Dokument
UMA 148
Rev
1
Page
5 (6)
Figure 2. An example of Automatic Zero Point Calibration
The Automatic Zero Point Calibration should be executed after installation and at least once a
year.
Trouble shooting
The yellow LED does not start to flash. The sensor does not enter calibration mode within three
minutes.
1. The absorber of the zero gas bag is not fresh. Remove the old absorber and refill the bottle with
fresh. The absorber is corrosive! Be careful and wear eye protection goggles.
2. The flow of the zero gas is too small or air is leaking into the sensor. The gas flow must be about
0,5 l/min.
3. Push the push button on the PCB for ten seconds (until the red LED is lit) to force manual zero
point calibration. Please check the gas before pushing the push button since the calibration is
executed even if the gas is not good enough.
Contact the dealer if the sensor still does not enter the calibration mode.
0
100
200
300
400
500
600
700
800
0
50
100
150
200
250
300
350
p
p
m
C
O
2
Time seconds
Normal
measurement
Zero gas
Yellow LED
flashes
Automatic Zero
Point Calibration
is reached
Phase 1 Check
calibration conditions
Phase 2 Acknowledgement period
Calibration is executed The yellow
LED flashes four times The red LED
is lit The relay is closed