ProSoft Technology ILX56-MM - Manual (Page 58)

Configure the ILX56-MM module ILX56-MM ♦ ControlLogix Platform
User Manual InRAx Message Manager for Industrial Communication
Page 58 of 112 ProSoft Technology, Inc.
February 6, 2012
3.5.1 Hysteresis Example
Compare Value 1 = Tag1
Condition = EGT
Compare Value 2 = 212.0
Tolerance = 12.0
Trigger fires once when Tag1 > 212.0.
Trigger arms when Tag1 <= (212.0-12.0).
Trigger fires again once when Tag1 > 212.0.
3.5.2 Range Example
Compare Value 1 = Tag1
Condition = EQ
Compare Value 2 = 212.0
Tolerance = 2.0
Trigger fires when 210.0 <= Tag1 <= 214.0
3.5.3 Trigger Scanning
Triggers are evaluated by the scanner at the rate specified by the Scan Period
attribute. If the Trigger Condition evaluates to TRUE (nonzero), the Trigger is
fired and any associated Transfer Lists are executed.
If multiple Transfer Lists are specified, they are executed simultaneously. After a
Trigger fires, it is disabled until all of the specified Transfer Lists are completed. It
is possible for multiple Triggers to simultaneously fire a single Transfer List.
If an asynchronous Trigger attempts to fire a currently executing Transfer List,
the Transfer List will be marked as pending and restarted as soon as it
completes. The associated Trigger will be disabled until the pending Transfer
Lists start and complete.
If an error occurs while reading the Trigger Compare Value 1, or Compare Value
2 tags, the error will be placed in the active error list, the error will be logged, and
the Trigger will be disabled for a period (usually 5 seconds, to prevent excessive
error logging). If or when a retry of the failed Compare Value 1 / Compare Value
2 read succeeds, the active error will be cleared, but the log entry will remain.