Functions
3.2 Option handling without reserve modules
3.2
Option handling without reserve modules
3.2.1
Principle of operation of option handling without RESERVE modules
60B
Principle
In the case of option handling without RESERVE modules, the configuration data are
insufficient to compare the preset configuration with the actual configuration. In addition,
information about the existing options is still required. This must be sent via the user data to
the IM151-1. In order to be able to receive the user data, the IM151-1 initially goes formally
into cyclic data exchange after the configuration data have been received. However, direct
I/O access does not yet take place. Output data are rejected, the input data are zero. The
IM151-1 only responds to the output data that you have to connect to a power module (O or
SO). A preset-actual test isn't possible until this option information is available. Only after this
can the I/O devices be operated.
Since the option information is stored retentively in the IM151-1, this intermediate state only
exists during the first commissioning or reconfiguration/retrofitting.
Please note the following:
● Data record requests to option slots that do not exist induce a fault (80B0).
● If the IM151-1 is operated without configuration or without a CPU (DP master), it supplies
the configuration as it exists. This is relevant for wiring test tools, since the actual slot
numbers, without gaps from 1 to n, are used there for status/control.
● There are no limitations when "packing" digital modules. Theoretically, the module to
which the byte address is assigned in the preset configuration can be missing in the
structure.
Note
The configured slot numbers (slot numbers in data records, and for events such as
diagnostics and interrupts) always apply for slot addressing.
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Interface module IM151-1 STANDARD (6ES7151-1AA06-0AB0)
Manual, 07/2015, A5E01075950-AD