Siemens MICROMASTER 420 Reference Manual page 71

Table 3-9
1
2
3
4
6
7
8
9
Table 3-10
187.50
500.00
500.00
12000.00
The shield of the cable must be connected to the housing of the SUB-D connector.
A segment can be extended by using RS485 repeaters.
Recommendation: SINEC L2 repeater RS485 (Order No.: 6ES7972-0AA00-0XA0).
For reliable operation of the serial bus system, the cable must be terminated at
both ends using terminating resistors. For operation at 12MBd, cables must be
terminated in connectors with a built-in damping network. Additionally, for 12 MBd
operation, no stub length from the main bus cable is allowed.
Suitable SINEC-L2 DP connectors and cable for reliable operation up to 12 MBd
are listed below in Table 2-13:
Table 3-11
6ES7 972-0BB10-0XA0
6ES7 972-0BA10-0XA0
6XV1830-0AH10
A floppy disk is supplied with the PROFIBUS module containing the handbook and
2 data files for configuring the relevant PLC system.
MICROMASTER 420 Reference Manual
Issue A1
Assignment of the PROFIBUS SUB-D socket connector
Not connected (NC)
NC
Send- and receive line RS 485, two wire, positive
differential input/output B/P
Request to send (RTS)
5V isolated power supply for termination resistors
NC
Send and receive line, RS 485, two wire negative
differential input/output A/N
NC
Maximum Cable Lengths for Data Transfer Rates
9.60 1200
19.20 1200
93.75 1200
1000
400
200
100
Order Numbers for Connectors and Cables
Bus Connector with PG interface
Bus connector without PG interface
Bus cable 20m-1000m
63