CTI 2500-C100, Инструкция по установке и эксплуатации

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CTI 2500 Installation and Operation Guide V2.8 55
6.3.1 Discrete Scan Mode
The CTI 2500 supports the following discrete scan modes.
Mode Description
PROGRAM When the Discrete Scan is in PROGRAM mode, the RLL tasks do not execute.
However, the NORMAL I/O and Special Function I/O tasks continue to operate
normally.
RUN When the PLC is in RUN mode, all discrete scan elements are executing.
EDIT This sub-mode is automatically selected when you modify an RLL program
while the controller is in RUN mode.
While the controller is in EDIT mode, you can modify the RLL source while the
non-modified RLL continues to execute. When you change to RUN mode after
editing, the RLL will be recompiled. During this time, which can take several
seconds, the I/O will be frozen at the last state. Should the compile fail, the
controller will be placed in PROGRAM mode.
6.3.2 Analog Scan Mode
The Analog Scan Mode is called the Loop Processor mode by some programming software.
You can select the following Analog Scan Modes:
Mode Description
PROGRAM When the Analog scan is placed in PROGRAM mode, the Loop, Alarm, and
Special Function Program/Subroutine tasks do not execute. Nothing will be
queued for execution. Other analog tasks, including communication tasks and
the diagnostics task, continue to operate normally.
THE ANALOG SCAN CANNOT BE PLACED IN PROGRAM MODE WHILE
THE DISCRETE SCAN IS IN RUN MODE.
RUN When the Analog Scan is in RUN mode, all analog tasks are running and
enabled control blocks are queued for execution.
HALT When the Analog Scan is placed in HALT mode, the Loop, Alarm and Special
Function Program/Subroutine tasks will be suspended. However, the enabled
control blocks will continue to be queued for execution.
When the analog scan mode is changed from HALT to RUN mode, task
execution will resume.
6.3.3 Scan Mode Locking
The Discrete and Analog scan modes are automatically locked when both scan modes are
place in PROGRAM mode. The scan modes are automatically unlocked when the analog scan
is placed in RUN mode while the discrete scan is in PROGRAM mode. You can manually lock
and unlock the scans when both scans are in RUN mode.