Siemens Simatic S7-300 CPU 31xC Series User Manual

Glossary
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05
Glossary-17
PROFINET IO System
See PROFINET IO Controller
See PROFINET IO Device
PROFINET IO controller with assigned PROFINET IO devices.
PROFINET node
A PROFINET node always has at least one Industrial Ethernet port. A PROFINET node can
also have a PROFIBUS port, that is, as master with proxy functionality. In exceptional
circumstances, a PROFINET node can also have more than one PROFIBUS port (for
example the CP 5614).
Programming device
Basically speaking, PGs are compact and portable PCs which are suitable for industrial
applications. Their distinguishing feature is the special hardware and software for SIMATIC
programmable logic controllers.
Proxy
See PROFINET node
The PROFINET device with proxy functionality is the substitute for a PROFIBUS device on
Ethernet. The proxy functionality allows a PROFIBUS device to communicate not only with
its master but also with all nodes on PROFINET.
You can integrate existing PROFIBUS systems in PROFINET communication, for example
with the help of an IE/PB Link or a CPU 31x-2 PN/DP. The IE/PB Link then handles
communication over PROFINET as a substitute for the PROFIBUS components.
Currently, you can include DPV0 slaves in PROFINET in this way.
Proxy functionality
See Proxy
RAM
Work memory is a RAM memory in the CPU accessed by the processor during user program
execution.
RAM (Random Access Memory) is a semiconductor read/write memory.

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)