Emerson PACSystems RX3i User Manual page 64

PACSystems™ RX3i and RSTi-EP CPU Reference Manual
GFK-2222AK
Scan Parameters
Backplane (Available only when Sweep Mode is set to Normal. Read-only if the Backplane
Communications Communications Window Mode is set to Complete.) The maximum execution time for
Window Timer the Backplane Communications Window per scan. This value can be greater than the
(ms) value for the watchdog timer.
The valid range and the default depend on the Backplane Communications Window
Mode:
▪
▪
Background (Available only when Sweep Mode is set to Normal.) The maximum execution time for
Window the Background Communications Window per scan. This value cannot be greater than
Timer (ms) the value for the watchdog timer.
Valid range: 0 through 255
Default: 0 (5ms for Redundancy CPUs)
Sweep Timer (Available only when Sweep Mode is set to Constant Sweep.) The maximum overall PLC
(ms) scan time. This value cannot be greater than the value for the watchdog timer.
Some or all of the windows at the end of the sweep might not be executed. The
windows terminate when the overall PLC sweep time has reached the value specified
for the Sweep Timer parameter.
Valid range: 5 through 2550 ms, in increments of 5 ms. If the value entered is not a
multiple of 5ms, it is rounded to the next highest multiple of 5ms.
Default: 100.
Window Timer (Available only when Sweep Mode is set to Constant Window.) The maximum combined
(ms) execution time per scan for the Controller Communications Window, Backplane
Communications Window, and Background Communications Window. This value
cannot be greater than the value for the watchdog timer.
Valid range: 3 through 255, in increments of 1.
Default: 10.
CPU Configuration
Complete: There is no time limit. The Backplane Communications Window Timer
parameter is read-only.
Limited: Valid range: 0 through 255ms. Default: 255. (10ms for Redundancy CPUs.)
Section 3
October 2019
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