Forcing Values In The Cpu; Using The Force Table - Siemens S7-1200 System Manual
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Also See for S7-1200:
- Operating instructions manual (132 pages) ,
- Programming manualline (74 pages) ,
- Manual (46 pages)
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14.11.5
Forcing values in the CPU
14.11.5.1
Using the force table
A force table provides a "force" function that overwrites the value for an input or output point
to a specified value for the peripheral input or peripheral output address. The CPU applies
this forced value to the input process image prior to the execution of the user program and to
the output process image before the outputs are written to the modules.
Note
The force values are stored in the CPU and not in the force table.
You cannot force an input (or "I" address) or an output (or "Q" address). However, you can
force a peripheral input or peripheral output. The force table automatically appends a ":P" to
the address (for example: "On":P or "Run":P).
In the "Force value" cell, enter the value for the input or output to be forced. You can then
use the check box in the "Force" column to enable forcing of the input or output.
In the force table, you can monitor the status of the forced value for an input. However, you
cannot monitor the forced value of an output.
You can also view the status of the forced value in the program editor.
Note
When an input or output is forced in a force table, the force actions become part of the
project configuration. If you close STEP 7, the forced elements remain active in the CPU
program until they are cleared. To clear these forced elements, you must use STEP 7 to
connect with the online CPU and then use the force table to turn off or stop the force function
for those elements.
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG
Use the "Start or replace forcing" button to force the value of the tags in the force
table. Click the "Stop forcing" button to reset the value of the tags.
14.11 Monitoring and modifying values in the CPU
Online and diagnostic tools
801
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