Configuring Hardware and Communication Connections STEP 7.pdf

1 Basics of Configuring Hardware with
STEP 7
1.1 Introduction to Configuring Hardware
Configuring
The term "configuring" refers to the arranging of racks, modules, distributed I/O
(DP) racks, and interface submodules in a station window. Racks are represented
by a configuration table that permits a specific number of modules to be inserted,
just like a real rack.
In the configuration table, STEP 7 automatically assigns an address to each
module. You can change the addresses of the modules in a station if the CPU in
the station can be addressed freely (meaning an address can be assigned freely to
every channel of the module, independent of its slot).
You can copy your configuration as often as you like to other STEP 7 projects,
modify it as necessary, and download it to one or more existing plants. When the
programmable controller starts up, the CPU compares the preset configuration
created in STEP 7 with the actual configuration of the plant. Any errors are
therefore recognized immediately and reported.
Assigning Parameters
The term "assigning parameters" refers to the following:
• Setting properties for programmable modules in a local configuration and in a
network. For example: a CPU is a programmable module. Its watchdog time is a
parameter you can set.
• Setting bus parameters, master and slave parameters for a master system
(PROFIBUS) or making other settings for exchanging data between
components.
The parameters are downloaded to the CPU and transferred during startup by the
CPU to the respective modules. Modules can easily be replaced because the
parameters set with STEP 7 are automatically downloaded to the new module
during startup.
Configuring Hardware and Communication Connections with STEP 7
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