Glossary
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
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Switch
PROFIBUS is a linear network. Communication participants are connected by a passive line:
the bus.
The Industrial Ethernet, on the other hand, consists of point-to-point connections: each
communication participant is connected exactly and directly to one other communication
participant.
If a communication participant is connected with several other communication participants,
then this communication participant is connected to the port of an active net component: the
switch. Other communication participants (also switches) can now be connected to the other
ports of the switch. The connection between a communication participant and the switch
remains a point-to-point connection.
This means a switch regenerates and distributes the signals it receives. The switch "learns"
the Ethernet address(es) of a connected PROFINET device or other switches and forwards
only those signals that are intended for the connected PROFINET device or the connected
switch.
A switch has a certain number of ports. Connect only one PROFINET device or another
switch to each port.
Thread length
Air gap and creepage distance (air gap = shortest distance between two components in air.
Creepage distance in air = shortest distance in air between two conductive parts along the
surface of an insulating material)
