YOKOGAWA IR800G, User Manual

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IM 11G06A01-02EN
5-17
5. SCREENS
1st Edition : Oct. 27, 2023-00
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Setting range
Alarm value: 10 to 1000 ppm (default 500 ppm)
Alarm count: 1 to 99 times (default 5 times)
Hysteresis: 0 to 20% FS (default 0% FS)
% FS is the ratio of the upper range of CO to 100%.
Example of Peak Alarm Operation
(2) Reached the Alarm count: 4 times/hour,
Open (OFF)
(1)Reached the Alarm count: ５ times/hour,
Closed (ON)
current time 1 hour ago 2 hour ago 3 hour ago
Alarm value
measured value
Peak count
alarm
Figure 5.7
Counts up when the CO instantaneous value exceeds the peak concentration. If that peak count
appears more than the set number of times per hour, the peak count alarm is turned "ON". When
the number of peaks is less than the set number of times per hour, the alarm is turned "OFF".
In the above figure, the peak count alarm is turned "ON" in the because 5 peaks
appeared in 1 hour. The time from (1) to (2) remains "ON" because the peak occurs
more than 5 times per hour. The peak count alarm is turned "OFF" when 4 times per hour at (2).
The hysteresis operation is similar to the hysteresis of the alarm setting and prevents chattering
when the gas to be measured is unstable near the peak concentration.
* Peak counting is not performed for 10 minutes after power-on.
Forced cancellation of peak count alarms
To forcibly cancel the peak count alarm, either display the CO Peak Count dialog from the
measurement screen and press the Reset button to set the peak count to 0 (see 4.4
General operation of display/operation panel), or turn the peak alarm setting to OFF". When the
peak alarm is turned "ON", the peak count will start from zero.