GE PACSystems RX7i - Page 129

Chapter 3. CPU Configuration
118 PACSystems* RX7i, RX3i and RSTi-EP CPU Reference Manual GFK-2222AD
Scan Parameters
Controller
Communications
Window Timer
(ms)
(Available only when Sweep Mode is set to Normal. Read-only if the Controller
Communications Window Mode is set to Complete.) The maximum execution time for the
Controller Communications Window per scan. This value cannot be greater than the value
for the watchdog timer.
The valid range and default value depend on the Controller Communications Window
Mode:
▪ Complete: There is no time limit.
▪ Limited: Valid range: 0 through 255ms. Default: 10.
Note: This parameter corresponds to the Programmer Window Timer parameter on a
Series 90-70 PLC.
Backplane
Communication
Window Mode
(Available only when Sweep Mode is set to Normal.) Execution settings for the Backplane
Communications Window.
Choices:
Complete: The window runs to completion. There is no time limit.
Limited: Time sliced. The maximum execution time for the Backplane Communications
Window per scan is specified in the Backplane Communications Window Timer parameter.
Default: Complete.
Backplane
Communications
Window Timer
(ms)
(Available only when Sweep Mode is set to Normal. Read-only if the Backplane
Communications Window Mode is set to Complete.) The maximum execution time for the
Backplane Communications Window per scan. This value can be greater than the value for
the watchdog timer.
The valid range and the default depend on the Backplane Communications Window Mode:
▪ 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.)
Background
Window
Timer (ms)
(Available only when Sweep Mode is set to Normal.) The maximum execution time for the
Background Communications Window per scan. This value cannot be greater than the
value for the watchdog timer.
Valid range: 0 through 255
Default: 0 (5ms for Redundancy CPUs)
Sweep Timer
(ms)
(Available only when Sweep Mode is set to Constant Sweep.) The maximum overall PLC
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.