Siemens SIMATIC NET PROFIBUS User Manual
Infrared Link Modul (ILM)
6ZB5530–3AC30–0BA1
11
Copyright
by Siemens
5.2.1
Point–to–Point–Link
Infrared
transmission link
0.5 to 15 m
transmission link
0.5 to 15 m
PROFIBUS
master network segment
master network segment
PROFIBUS
slave network segment
slave network segment
Slave
Master
Master
Master
Slave
Slave
Slave
ILM
ILM
Figure 2:
Point-to-Point Link with Two PROFIBUS ILMs
Figure 2 describes the typical layout of a PROFIBUS network with master and slave nodes and an infrared
transmission link with two PROFIBUS ILMs. The infrared transmission link is implemented as a point-to-point
link by the two PROFIBUS ILMs. In this situation, the two PROFIBUS ILMs replace a cable connection
between the two network segments. Remember that only slave nodes are permitted in the slave network
segments.
transmission link with two PROFIBUS ILMs. The infrared transmission link is implemented as a point-to-point
link by the two PROFIBUS ILMs. In this situation, the two PROFIBUS ILMs replace a cable connection
between the two network segments. Remember that only slave nodes are permitted in the slave network
segments.
+
Make sure that the terminating resistors are activated at the segment ends (either in the bus
connector or in a PROFIBUS ILM).
connector or in a PROFIBUS ILM).
Cascading is a further application for a point-to-point link.
Note
This “cascading with PROFIBUS ILM” mode is possible, but does involve a risk when operating PROFIBUS.
The transmission using an infrared link is generally more susceptible to problems than transmission via cable
(optical or electric).
The transmission using an infrared link is generally more susceptible to problems than transmission via cable
(optical or electric).