Installing/Mounting
4.3 Connecting a CU240S via USS on RS485
Control Units CU240S
Operating Instructions, 07/2008 - FW 3.2, A5E00766042B AD
35
4.3
Connecting a CU240S via USS on RS485
Socket
The Control Units CU240S have a 9-pin female sub-D socket for connecting the inverter via
an RS485 interface.
Table 4-1
PIN assignment of the 9-pin sub-D socket
Pin Designation
Description
1
-
Unused
2
-
Unused
3
RS485P
Receive- and transmit signal (+)
4
-
Unused
5
0 V
Ground reference
6
-
Unused
7
-
Unused
8
RS485N
Receive- and transmit signal (-)
9
-
Unused
X
Screen (casing) Potential equilisation
Connector
A standard 9 pin sub-D connector can be used for USS connection via RS485.
Table 4-2
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".