Siemens SIMATIC S7-300 Module data Hardware And Installation Manual

Configuring
S7-300 Programmable Controller Hardware and Installation
4-30 A5E00105492-01
4.10.2 Basics
MPI, PROFIBUS-DP, PtP
Since these subnets are the most commonly used for S7-300 CPUs, we shall take
a closer look at them.
Declaration: Device = Node
In the following, all networked devices are referred to as nodes.
Segment
A segment is a bus link between two terminating resistors. A segment can include
up to 32 nodes. It is also limited by the permissible line length, depending on the
transmission rate.
Transmission rate
These maximum transmission rates are possible:
• MPI
– 12 Mbps with CPU 318-2 DP
– 187.5 Kbps with all other CPUs
• PROFIBUS-DP: 12 Mbps
• PtP:
– Half duplex: 38.4 Kbps
– Full duplex: 19.2 Kbps
Number of nodes
Maximum possible number of nodes per subnet:
Table 4-11 Subnet nodes
Parameter MPI PROFIBUS-DP PtP
Number 127 126
1)
2
Addresses 0 to 126 0 to 125 -
Remarks Default: 32 addresses
Reserved are:
• address 0 for PG
• address 1 for OP
of those:
• 1 Master (reserved)
• 1 PG connection
(address 0 reserved)
• 124 slaves or other
masters
-
1) Note CPU-specific maximum specifications in the respective CPU manual.
MPI/PROFIBUS-DP addresses
To ensure that all nodes can intercommunicate, you must assign them an address:
• In the MPI network: an "MPI address"
• In the PROFIBUS-DP network: a "PROFIBUS-DP address"

Siemens SIMATIC S7-300 Module data Specifications

General

Series	S7-300
Manufacturer	Siemens
Protection Class	IP20
System	SIMATIC S7-300
Digital Inputs	Varies by module
Digital Outputs	Varies by module
Analog Inputs	Varies by module
Analog Outputs	Varies by module
Central Processing Unit	Varies by CPU model
Supply Voltage	24V DC or 120/230V AC
CPU Type	Varies (e.g., CPU 312, CPU 315, etc.)
Memory	Varies by CPU model
Communication Interfaces	MPI, PROFIBUS
Programming Languages	LAD, FBD, STL, SCL, GRAPH
Operating Temperature	0°C to 60°C
Storage Temperature	-40°C to 70°C
Relative Humidity	10% to 95% (non-condensing)