Network Rules - Siemens SINUMERIK 840Di Manual

7 PROFIBUS DP Communication

7.2 Network rules

7.2 Network rules
Example:
PROFIBUS DP
network
installation
7-210
The following basic rules must be observed:
1. The bus line must be terminated on both ends. To this aim, enable the ter-
minator in the PROFIBUS DP connector of the first and of the last nodes
and disable the remaining terminators.
Notice
Only two enabled terminating resistors are permitted per bus line.
2. At least 1 terminator must be supplied with 5V voltage.
For this, the PROFIBUS DP connector with inserted terminating resistor
must be connected to a powered device.
3. No tap lines may be routed along PROFIBUS DP.
4. Each PROFIBUS node must first be connected and then enabled.
When disconnecting a node, first disable the connection, then remove the
connector.
5. The cable length of a PROFIBUS DP bus segment may be max. 100m.
Field device
SIMATIC ET200
OFF
PROFIBUS DP
(max. of 100m)
PROFIBUS DP
OFF
Drive
SIMODRIVE 611
universal
Fig. 7-3 Example of a PROFIBUS DP network installation
Field device
SIMATIC ET200
ON
ON
OFF
ON
Drive
SIMODRIVE 611
universal
OFF
 Siemens AG, 2003. All rights reserved
SINUMERIK 840Di Manual (HBI) – 06.03 Edition
06.03
SINUMERIK 840Di
PCU
MCI board
Terminating resistor in
the connector enabled
Terminating resistor in
the connector not en-
abled