Maintenance, Gas inlet – ROTRONIC CF8-W-Disp-AL User Manual
Page 7
Dokument
UMA 145
Rev
3
Page
7 (8)
Maintenance
The CF8-W-Disp-AL
is basically maintenance free. An internal self-adjusting
calibration function takes care of normal long term drift associated to the CO
2
sensor.
To secure the highest accuracy, a time interval of five years is recommended
between CO
2
calibrations, unless some special situations have occurred. A zero
calibration can be performed by use of pure nitrogen or air that has passed through a
chemical absorber and a PC together with the UIP software version 4.3 (or higher).
The Zero Calibration Bag can be used to produce carbon dioxide free air. The
software can be free downloaded from www.rotronic.com. The RS232-cable and the
zero calibration bag can be ordered from Rotronic. The cable is to be connected to
the UART port slide connector. For change of control parameters and re-calibration
of CO
2
this PC tool has to be used. The check can be done on site without interfering
with the ventilation system.
This is for sensors with measuring ranges between 0-3000 ppm and 0-4%:
When a zero calibration shall be executed a plastic tube with 2.2 mm outer diameter
and 0,8 mm inner diameter shall be inserted in marked holes of the sensor. Plastic
tubing is connected to the tube. The gas flow should be between 0.3 and 1.0 l/min.
Figure 4 Part of the PCB with holes for gas inlets marked.
Gas inlet
Gas inlet