Yokogawa Multi Channel Oxygen Analyzer System ZR22/AV550G - Manual (Page 160)

IM 11M12D01-01E 9-10
9.3 Performing Calibration
Note
1) Perform calibration under normal working conditions (e.g. continuous operation with
sensor mounted on furnace).
2) Perform both Span and Zero calibration for best resultant accuracy.
3) When instrument air is used for the span calibration, remove the moisture from the
instrument air at a dew-point temperature of -20
؇ C and also remove any oily mist
and dust from that air.
4) If dehumidifying is not enough, or if foul air is used, the measurement accuracy will
be adversely affected.
9.3.1 Performing Manual Calibration
To perform manual calibration, you open or shut calibration gas valves following
messages on the display. Solenoid valves can be opened and closed automatically at the
same time the messages are displayed on the display. For details, see Sec. 7.9.2,
9.3.2 Semi-Automatic Calibration
Semi-automatic calibration is started either from the display or by external contacts.
When started from the display, only the channel selected on the display is calibrated.
When started by an external contact, all working channels can be calibrated one channel
after another. Here we give an example of the procedure for both of these cases, with
both Span and Zero calibration selected.