YOKOGAWA IR800G, User Manual

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IM 11G06A01-02EN
5-14
5. SCREENS
1st Edition : Oct. 27, 2023-00
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Items to set
Hysteresis Function to prevent chattering of alarms near alarm setpoints.
Common to all alarms.
Set the following items for each alarm (1~6)
On/Off On" to enable the alarm function, "Off" to disable it.
Target Ch Set the channel for the alarm. The same Ch. No. can be set for multiple
alarms.
H-Limit Set the upper limit (concentration) of the alarm
L-Limit Set the lower limit (concentration) of the alarm
Contact Select from 5 options: upper limit, lower limit, upper or lower limit, upper
or lower limit, lower or upper limit, lower or lower limit
H-limit, HH-limit; Alarm ON only when the value exceeds the H-limit value.
L-Limit, LL-Limit; Alarm ON only when the value falls below the LL-Limit
value.
H-Limit or L-Limit; Alarm ON when the value is above the H-Limit or below
the L-Limit.
NOTE
• Set the value so that H-Limit > L-Limit. In addition, set the value so that (H-Limit value - L-Limit value) >
hysteresis width. If you want to set the H-Limits below the already set L-Limit, lower the L-Limit at first, and
then set the H-Limit. Do the equivalent for the L-Limit value.
• In error checking during setup, the judgment as to whether H-Limit/L-Limit is within the range of the range is
made when On/Off is On and the range is valid. (Range 2 is enabled when the number of ranges is 2 in the
Range setting. For more information on range setting, see 5.2.1 Channel settings for more information on
range settings)
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Setting range
Hysteresis: 0 to 20% FS
H-Limit/L-Limit: 0 to 100% FS (Settable for each range)
FS (Full Scale) is the ratio of the range width of each component to 100%.
Hysteresis behavior (for upper limit alarms)
As shown in the figure below, the alarm turns "ON" when the H-Limit value is exceeded. After the
alarm turns "ON", it turns "OFF" when the value falls below the hysteresis width preset from the
H-Limit value.
H-Limit
ON (Closed)
OFF (Open)
Hysteresis
width
Alarm
Figure 5.5