Rockwell Automation 1756-IH16ISOE ControlLogix Sequence of Events Module - Manual (Page 64)

Publication 1756-UM528A-EN-P - April 2004
5-12 Using the Sequence of Events Module Features
• Scenario #3 – The input turns ON but turns OFF before 2ms
(length of the input filter setting) elapses. In this case, the
Sequence of Events module continues to scan the input every
25
µs for 4x the length of the input filter setting (i.e., for 8ms).
In those 8ms, the input never remains ON for at least 2ms
(i.e., the input filter setting). In this case, the module
considers the transition invalid and drops the data
timestamped at the original transition.
Figure 5.3
Use the Configuration tab in RSLogix 5000 to configure Input
Filters, as shown in the example below.
0 1 2 3 4 5 6 7 8
Time in milliseconds
43671
Input turns OFF before
2ms have elapsed. In none of these time periods is
the input ON for at least 2ms
After 8ms (i.e., 4x the input filter setting),
the module drops the data recorded at the
original transition. If an RPI occurs during
this 8ms, the module sends the controller its
current valid input data; the data that’s sent
does not include data from the transition
describes in this graphic because the
timestamp has not been validated.
The next time the input turns ON, the
module records the transition as
timestamp #1.
Input turns ON;
timestamp #1
Type the filter times or use the
increase/decrease arrows to
configure the Input Filter Time.
The Input Filter Time range is 0
to 50ms.