Echelon i.LON 100 e2 Internet Server - Manual (Page 100)

i. LON 100 Internet Server Programmer’s Reference 7-11
Property Description
<SCPThystHigh1>
<SCPThystHigh2>
<SCPThystLow1>
<SCPThystLow2>
When an alarm occurs based on one of the offest limits described above, the
value of the input data point must reach the hysteresis value for that limit
before the alarm can be cleared, and another alarm can be generated based
on that offset limit.
This allows you to set up an Alarm Generator that will trigger an alarm
once each time the value of the input data point reaches a certain level, as
opposed to multiple times (which would occur each time the data point was
updated and its value remained within the range specified by the offset
limit).
Enter a scalar value for each of these properties. These values define the
hysteresis level that will be used for each alarm offset limit. For a more
detailed description of the hysteresis fields and how they relate to the
offset limit values, see Hysteresis Levels and Offset Limits on page 7-13.
If you use the
i. LON 100 Configuration Software to modify the
configuration of an Alarm Generator after creating it with the SOAP/XML
interface, all four hysteresis properties will be reset to the value chosen for
<SCPThystHigh1>.
NOTE: If you use the AlarmGeneratorGet function to return the
configuration of an Alarm Generator whose input data point uses the
format type SNVT_temp_p#US or SNVT_temp#US, then the values of
these properties will be displayed using the SNVT_temp_f#US format. This
rule applies to all formats that use the #US specifier.
7.2.1.2.1 Alarm Priority Levels
You can select a priority level for the Alarm Generator by filling in the
<UCPTalarmPriority> property. When doing so, you must reference each priority level with
the identifier listed in Table 23.
Each time an Alarm Generator generates an alarm, the priority_level field of the alarm data
points chosen for the Alarm Generator will be updates to the priority level chosen here.
Table 23 Alarm Priority Levels
Identifier Notes
PR_LEVEL_0 Lowest alarm priority level
PR_LEVEL_1
PR_LEVEL_2
PR_LEVEL_3 Highest alarm priority level
PR_1 Life Safety Fire Alarms
PR_2 Property Safety Fire Alarms
PR_3 Fire Supervisory Alarm
PR_4 Fire Trouble/Fault (Display)
PR_6 Fire Pre-Alarm, HVAC Critical Equipment Alarm
PR_8 HVAC Alarms (BACnet Priority 8)