Rockwell Automation 1769-OF4VI Compact I/O Isolated Analog Modules - Manual (Page 52)

Publication 1769-UM014B-EN-P - May 2010
3-14 Module Data, Status, and Channel Configuration for the Input Module
Figure 3.2 Alarm Deadbands
The value entered for a channel’s alarm deadband value must be within the
normal operating data range as set by the Input Data Format selected for that
channel. If an alarm deadband value is entered that is outside the normal
operating data range set for a channel, the module indicates a configuration
error.
The module also checks for an alarm deadband value that is less than 0 or large
enough to exceed one or both of the channel’s full range limits. When one of
these conditions occurs, the module changes the alarm deadband value that is
in violation to one that is allowed. A deadband value less than 0 is set at 0. A
deadband value that when added to the process alarm low data value or
subtracted from the process alarm high data value results in a value that
exceeds the full range limits of the channel is adjusted to the first, smaller value
that eliminates this full range violation.
43153
Low
High
Alarm Deadbands
Normal Input Range
High alarm turns OFF.
Low alarms turns OFF. Low alarms turns ON.
High alarm
turns ON.