Operating instructions

Communication
6.6 Communication via USS
Control Units CU240S
180 Operating Instructions, 10/2007, A5E00766042B AC
Connector
A standard 9 pin sub-D connector can be used for USS connection via RS485.
Table 6-38 Technical data of standard 9-pin sub-D connector for RS485
Standard 9 pin sub D connector
PG socket No
Max. baud rate 115200 baud
Outgoing cable unit 180°
Bus termination
The RS485 termination can be activated via switches on the housing of the SINAMICS
G120.
The bus termination switch is illustrated in figure "Control Units CU 240S" in section "Layout
and Block Diagram".
Cable Lengths and number of devices
Table 6-39 Max. number of devices and max. cable length
Baudrate in bit/s Max Number of Devices Max Cable Length
9600 32 1200 m
19200 32 1200 m
38400 32 1200 m
57600 32 1200 m
115200 (maximum baudrate) 30 1000 m