Siemens Simatic S7-300, Hardware And Installation Manual, Page: 26 / 242

Product overview
S7-300 Programmable Controller Hardware and Installation
3-4
A5E00105492-01
Components Function Illustration
SIEMENS
CPU
Accessory:
Front connectors (for CPUs with
integrated I/O)
... executes the user program; 5-
V supply for the S7-300
backplane bus; communicates
with other MPI network nodes via
MPI interface.
Additional properties of specific
CPUs:
•
DP master in a PROFIBUS
subnet
•
DP slave in a PROFIBUS
subnet
•
Technological functions
•
Point-to-point communication
Signal modules (SM)
(Digital input modules, digital
output modules, digital I/O
modules, analog input modules,
analog output modules, analog
I/O modules)
Accessory:
Front connectors
... adapt different process signal
levels to the S7-300
Function modules (FM)
Accessory:
Front connectors
... for time-critical process signal
processing tasks with high
memory load, e.g. positioning or
controlling
Communication processor (CP).
Accessory:
Connecting cable
... relieves the CPU of
communication load, e.g.
CP 342-5 DP connection to
PROFIBUS-DP
SIMATIC TOP connect
Accessory:
Front connector module with
ribbon cable terminals
... for wiring of digital modules
Interface module (IM)
Accessory:
Connecting cable
... interconnects the individual
tiers of an S7-300
PROFIBUS cable with bus
connector ... interconnects nodes on an MPI
or PROFIBUS subnet