Siemens Simatic S7-300 CPU 31xC Series User Manual

S7-300 components
3.2 Overview of the vital modules of an S7-300
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05
3-3
Component Function Illustration
Signal modules (SM)
• Digital input modules
• Digital output modules
• Digital I/O modules,
• Analog input modules
• Analog output modules
• Analog I/O modules
Accessories:
• Front connectors
The SM matches different process
signal levels to the S7-300.
Function modules (FM)
Accessories:
• Front connectors
The FM performs time-critical and
memory-intensive process signal
processing tasks.
Positioning or controlling, for example
Communication processor (CP)
Accessories: Connecting cable
The CP relieves the CPU of
communication tasks.
Example: CP 342-5 DP for connecting
to PROFIBUS DP
SIMATIC TOP connect
Accessories:
• Front connector module with ribbon
cable terminals
Wiring of digital modules
Interface module (IM)
Accessories:
• Connecting cable
The IM interconnects the various rows
in an S7-300
PROFIBUS cable with bus connector Interconnect the nodes of an MPI or
PROFIBUS subnet
PG cable Connects a PG/PC to a CPU

Siemens Simatic S7-300 CPU 31xC Series Specifications

General

Series	S7-300 CPU 31xC
Power Supply	24 V DC
Communication Interfaces	MPI, PROFIBUS DP
Programming Languages	LAD, STL, FBD, SCL
Operating Temperature	0°C to +60°C
Memory	48 KB - 512 KB
Dimensions	40 x 125 x 130 mm (varies by model)