GE Hydran 201i Instruction Manual page 163

Hydran* 201i Instruction Manual
• GasAlr H and GasAlr HH: Gas High and High-High alarm set points.
• GasAlr Delay: The gas alarms delay determines the period of time during
which the gas level must exceed the gas High and High-High alarm set points
in order to trigger the alarm. Accordingly, the gas level must get below the
alarm set point for the same amount of time in order to cancel the alarm.
Before setting these alarm set points, the readings of the Hydran 201i System should
be monitored over a minimum period of two weeks. A simple method to monitor this
value is to consult the Hydran 201Ti's historic data files using its keypad (see Section
5.5.1) or a host computer running the Hydran Host software.
Follow these rules:
• Adjust the High set point above the highest reading that was obtained.
• Adjust it low enough to detect the earliest sign of an abnormal increase of
gas.
• But set it at a value high enough to minimize unnecessary alarms.
Table 11-4 contains suggested guidelines for setting the gas level High alarm
condition, according to the maximum reading obtained during the monitoring period.
CAUTION
Hydran 201Ti Maximum Reading
(Obtained during the monitoring period)
Below 70ppm
From 70 to 400ppm
Above 400ppm
Table 11-4: Suggested Guidelines for Setting the Gas Level High Alarm Conditions
MA-033 Rev. 14.0, 12-Nov-18
This Chapter contains examples of how to set the gas alarm
parameters of the Hydran 201i System. The values used are
fictitious and do not correspond to any standard. General
Electric does not suggest nor recommend specific alarm set
points. It is solely the responsibility of the user to determine
the appropriate settings
Minimum Suggested Alarm Set Point
(to reduce the likelihood of false alarms)
100ppm
1.5 times the highest H201Ti reading
200ppm above the highest H201Ti reading
Page 163