1.8 Network Components - Siemens SIMATIC S5 Manual

System overview

1.8 Network components

Definition
Connecting the
bus
Electro-optical
conversion
Signal
amplification
1-16
You require network components
to connect the bus to a station,
to amplify the signal
and / or
to convert the signal to a fiber-optic medium.
There are several ways of connecting the bus to the station:
IP 20 bus connector (see Section 1.8.1)
IP 66/67 bus connector, e.g. for connection to ET 200C
If you want to bridge large distances with the field bus or ensure that data
traffic on the bus is not impaired by external interference, you should use
fiber-optic cables instead of copper cables.
Table 1-3 shows the maximum distances between two OLMs (Optical Link
Modules). You can cascade up to seven OLMs. See the manual en-
titled SINEC L2/L2FO Network Components for more details.
Table 1-3 Maximum distance between two OLMs (Optical Link Modules)
Baud rate
9.6 to 187.5 kbaud
500 kbaud
1500 kbaud
RS 485 repeaters are used to amplify the electric signal (see Section 1.8.2).
Optical Link Modules (OLMs) are used to amplify the optical signal up to
1.5 Mbaud.
Maximum distance between two OLMs
2.8 km
1.6 km
0.5 km
ET 200 Distributed I/O System
EWA 4NEB 780 6000-02a