Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 124)

IM 11M12A01-05E 9-7
9. Calibration
CAUTION
(1) When instrument air is used for the span calibration, remove the moisture from the
instrument air at a dew-point temperature of -208C and also remove any oily mist
and dust from that air.
(2) If dehumidifying is not enough, or if foul air is used, the measurement accuracy will
be adversely affected.
9.2.1.5Calibration Time
• When the calibration mode is in manual:
First set the output stabilization time. This indicates the time required from the end
of calibration to entering a measurement again. This time, after calibration, the
measurement gas enters the sensor to set the time until the output returns to normal.
The output remains held after completing the calibration operation until the output
stabilization time elapses. The calibration time set ranges from 00 minutes, 00
seconds to 60 minutes, 59 seconds. For more details, consult Section 8.3,”Setting
Output Hold.” When the calibration mode is semi-automatic, set the output stabiliza-
tion time and calibration time. The calibration time is the time required from starting
the flow of the calibration gas to reading out the measured value. The set calibration
time is effective in conducting both zero and span calibrations. The calibration-time
set ranges from 00 minutes, 00 seconds to 60 minutes, 59 seconds. Figure 9.4 shows
the relationship between the calibration time and output stabilization time.
Analog output remains hold
(when output remains hold)
Calibration start
(contact or switch input)
Span calibration
(span-gas valve open)
Zero-point calibration
(zero-gas valve open)
Analog output status
Calibration time
Calibration time
Stabilization
time
F9.4E.EPS
Figure 9.4 Calibration and Output-stabilization Time Settings
When the calibration mode is in automatic:
In addition to the above output stabilization time and calibration time, set the interval,
start date, and start time.
Interval means the calibration intervals ranging from 000 days, 00 hours to 255 days, 23
hours.
Set the first calibration day and the start-calibration time to the start date and start time
respectively. After the first calibration is carried out, the next calibration will be ex-
ecuted according to the preset calibration intervals.