Behavior During Operation - Siemens SIMATIC ET 200SP System Manual

Configuration control (option handling)

9.4 Behavior during operation

Special aspects relating to the transfer of the control data record to the interface module
● If you have enabled configuration control, the ET 200SP station is not ready for operation
without a control data record. As long as no valid control data record has been
transferred, the I/O modules are considered as failed by the CPU and exhibit substitute
value behavior. The interface module continues to exchange data.
● The control data record is stored retentively in the interface module. Note:
– If there have been no changes to the configuration, you do not need to rewrite the
– If you write a control data record with modified configuration to the interface module, it
9.4 Behavior during operation
Effect of discrepancy between station master and station option
For the online display and for the display in the diagnostics buffer (module OK or module
faulty), the station master is always used and not the differing station option.
Example: A module supplies diagnostic information. This module is configured in slot 4 in the
station master, but is inserted in slot 3 in the station option (missing module; see example in
the next section). The online view (station master) shows a faulty module in slot 4. In the real
configuration, the module in slot 3 indicates an error via an LED display.
Response when modules are missing
If modules are entered as not present in the control data record, the automation system
behaves as follows:
● Modules designated as not present in the control data record do not supply diagnostics
and their status is always OK. The value status is OK.
● Direct write access to the outputs that are not present or write access to the process
image of the outputs that are not present: Remains without effect; no access error is
signaled.
● Direct read access to the inputs that are not present or read access to the process image
of the inputs that are not present: Value "0" is supplied; no access error is signaled.
● Write data record to module that is not present: Remains without effect; no error is
signaled.
● Read data record from module that is not present: An error is signaled because a valid
data record cannot be returned.
162
control data record 196 during restart.
will result in a station failure in the distributed I/O system. The original data record 196
is deleted and the new data record 196 is saved retentively. The station will then
restart with the modified configuration.
Distributed I/O system
System Manual, 12/2015, A5E03576849-AF