Siemens SIMATIC S7-300 Module data Reference Manual

RS 485 Repeater
7-5
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
Isolation between bus segments
Bus segment 1 and bus segment 2 are galvanically isolated from each other. The
PG/OP interface is connected internally to the port for bus segment 1. Figure 7-2
shows the front panel of the RS 485 repeater.
24 VDC
L+ M PE M 5.2
SIEMENS
RS 485-REPEATER
ON
A1 B1 A1 B1
A2 B2 A2 B2
PG
OP
DP2
OFF
ON
DP1
Terminals for bus segment 1
Terminals for bus segment 2
PG/OP
interface
Isolation
Figure 7-2 Isolation between the Bus Segments
Amplification of the bus signals
The amplification of the bus signals takes place between the port for bus segment
1 or the PG/OP interface and the port for bus segment 2.

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)