Siemens SIMATIC C7-626, Монтаж, сборка, подключение

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Glossary-8
C7-626 / C7-626 DP Control Systems
C79000-G7076-C626-01
S
The scan cycle time is the time required by the
³
C7 to execute the
³
user
program once.
Signal modules (C7 I/O) form the interface between the process and the C7.
There are digital input and output modules and analog input and output
modules.
Programming software for creating user programs for SIMATIC S7
programmable controllers.
A STEP 7 application is a tool of
³
STEP 7, which is tailored to a specific
task.
Substitute values are values which are output to the process in the case of
faulty signal output modules or which are used in the user program instead of
a process variable in the case of faulty signal input modules. The substitute
values can be specified in advance by the user (for example, maintain old
value).
System diagnostics comprises the recognition, evaluation and signalling of
errors which occur within the programmable controller. Examples of such
errors include: program errors or module failures. System errors can be
indicated via LEDs or via STEP 7.
The system memory is integrated in the CPU and executed in the form of
RAM. The address areas (for example, timers, counters, bit memory) and
data areas required internally by the
³
operating system (for example,
backup for communication) are stored in the system memory.
T
The time-of-day interrupt belongs to one of the priority classes in the
program execution of the C7 CPU. It is generated at a specific date (or day)
and time (for example, 9:50 or every hour or every minute). A corresponding
organization block is then executed.
The time-delay interrupt belongs to one of the priority classes in SIMATIC
S7 program execution. It is generated when a timer has expired in the user
program. A corresponding organization block is then executed.
Scan Cycle Time
Signal Module
STEP 7
STEP 7
Application
Substitute Value
System
Diagnostics
System Memory
Time-Delay
Interrupt
Time-Of-Day
Interrupt
Glossary