Siemens SIMATIC NET OLM12M Description And Operating Manual page 51

6ZB5530–3AB00–0BA0/01
2 Introduction
The SIMATIC NET OLM12M optical link modules are intended for use in optical PROFIBUS field
bus networks. They allow the conversion of electrical PROFIBUS interfaces (RS 485) to optical
PROFIBUS interfaces and vice-versa. You can integrate the modules in existing PROFIBUS field
bus networks to make use of the well-known advantages of optical transmission techniques. It is
also possible to design a complete PROFIBUS field bus network using optical link modules in a
bus, star or ring topology.
Each OLM12M has three independent channels consisting of a transmitter and receiver section.
Channel 1 is an electrical port (RS 485) designed as a 4-wire terminal block with a shield clip.
Channels 2 and 3 are the optical ports. The fiber-optic cables are connected via duplex sockets.
The power supply is 24 V direct voltage.
LEDs signal the current status and any faults/errors during operation.
Figure 1: OLM12M Optical Link Module
Copyright Siemens AG 1997
1 = Power supply and signaling contact
2 = LED displays
3 = Switch for terminating resistor
4 = Channel 1: electrical, 4-wire terminal
block and shield clip
5 = Channel 2: optical, duplex socket
6 = Channel 3: optical, duplex socket
2
SIMATIC NET OLM12M