Overview Of The Vital Modules Of An S7-300 - Siemens Simatic S7-300 CPU 31xC Series Installation And Operating Instructions Manual

S7-300 components

3.2 Overview of the vital modules of an S7-300

3.2 Overview of the vital modules of an S7-300
You can choose from a number of modules for installing and commissioning the S7-300. The
most important modules and their functions are shown below.
Table 3-1 S7-300 components:
Component
Mounting rail
Accessories:
Shielding terminal
•
Power supply (PS) module
CPU
Accessories:
Front connectors (CPU 31xC only)
•
3-2
Function
S7-300 racks
The PS converts the line voltage
(120/230 VAC) into a 24 VDC operating
voltage, and supplies the S7-300 and
its 24 VDC load circuits.
The CPU executes the user program,
supplies 5 V to the S7-300 backplane
bus, and communicates with other
nodes of an MPI network via the MPI
interface.
Additional features of specific CPUs:
DP master or DP slave on a
•
PROFIBUS subnet
Technological functions
•
PtP communication
•
Ethernet communication via
•
integrated PROFINET interface
Illustration
SIEMENS
A CPU 31xC, for example
SIE ME NS
A CPU 312, 314, or 315-2 DP, for
example
A CPU 317, for example
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05