Siemens Simatic S7-300 CPU 31xC Series User Manual

Wiring
6.9 Wiring the MPI / PROFIBUS DP bus connectors
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05
6-15
6.9 Wiring the MPI / PROFIBUS DP bus connectors
6.9.1 Wiring the bus connector
Introduction
You need to network all the nodes you integrate into a subnet of your system. Information on
how to wire the bus connector can be found in the article below.
Wiring a bus connector with screw terminals
1. Strip the bus cable.
Details on stripped lengths are found in the product information supplied with the bus
connector.
2. Open the bus connector housing.
3. Insert the green and the red wire into the screw-terminal block.
Always connect the same wires to the same terminal (green wire to terminal A, red wire to
terminal B, for example).
4. Press the cable sheath into the clamp. Make sure that the shielding directly contacts the
shielding contact surfaces.
5. Screw-tighten the wire terminals.
6. Close the bus connector housing.
Wiring a Fast Connect bus connector
1. Strip the bus cable.
Details on stripped lengths are found in the product information supplied with the bus
connector.
2. Open the strain relief of the bus connector.
3. Insert the green and red wire into the open contacting covers.
Always connect the same wires to the same terminal (green wire to terminal A, red wire to
terminal B, for example).
4. Close the contacting cover.
This presses the conductors into the insulation displacement terminals.
5. Screw-tighten the strain relief clamp. Make sure that the shielding directly contacts the
shielding contact surfaces.

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)