Siemens SIMOTION D4 5-2 Series Commissioning And Hardware Installation Manual page 68

Connecting
3.7 Connecting PROFIBUS/MPI
● If you operate more than 32 nodes on a subnet, you must use RS 485 repeaters to
● Use RS 485 repeaters to connect ungrounded bus segments and grounded bus
● The maximum number of nodes per bus segment decreases with each RS 485 repeater.
● Up to 10 segments can be connected in a row (max. 9 repeaters).
● At least one terminator must be supplied with 5 V.
● Before inserting a new node on the subnet, you must switch off its supply voltage.
● The bus line of a segment must be terminated at both ends. This is achieved by switching
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connect the bus segments. More detailed information can be found in the description of
the RS 485 repeater, see the
In a PROFIBUS subnet, all segments combined must have at least one DP master and
one DP slave.
segments.
This means that when a bus segment contains an RS 485 repeater, the bus segment can
contain no more than 31 additional nodes. However, the number of RS 485 repeaters
does not affect the maximum number of nodes on the bus.
To accomplish this, the PROFIBUS DP connector with an activated terminating resistor
must be connected to a device that is switched on.
The station must be inserted first and then switched on.
When a station is disconnected, the connection must first be deactivated and then the
connector withdrawn.
on the terminating resistor in the PROFIBUS DP connector at the first and last node and
switching off the other terminating resistors.
S7-300 Automation Systems, Module Data
Commissioning and Hardware Installation Manual, 02/2012
Manual.
SIMOTION D4x5-2