Siemens SIMATIC NET PROFIBUS User Manual

2-6

PROFIBUS Networks SIMATIC NET

6GK1970-5CA20-0AA1 Release 2 05/2000

The optical PROFIBUS network with nodes having an integrated FO interface is
structured as a bus topology. The PROFIBUS nodes are interconnected in pairs
by duplex fiber-optic cables.

Up to 32 PROFIBUS nodes with integrated FO interfaces can be connected in
series in an optical PROFIBUS network. If a PROFIBUS node fails, the bus
topology means that all DP slaves on the side away from the DP master are no
longer obtainable for the DP master.

PG/PC/OP

2

Distances between 2

nodes:

Plastic FO cable up to 50 m

PCF FO cable up to 300 m

OBT

OBT

S7-400 with IM 467 FO

ET 200M with
IM 153-2 FO

S7-300

other 
nodes

1

1 FO cable

2 LAN cable for PROFIBUS

1

1

2

OP 25

 

Terminating resistor activated

2

Figure 2-2

PROFIBUS DP Network with Nodes Having Integrated FO Interfaces

For short distances, the preassembled 830-1T or 830-2 connecting cables can be
used as an alternative to the PROFIBUS cable.

An optical PROFIBUS network with a bus topology can be operated at the
following transmission rates:

9.6 Kbps, 19.2 Kbps, 45.45 Kbps, 93.75 Kbps, 187.5 Kbps, 500 Kbps, 1.5 Mbps
and 12 Mbps