
5. ROUTER DESIGN
5.9.2
RS232-RS485/422 interface
These interfaces are physically connected on five-pin and four-pin terminal block connec-
tors. The insulation strength is up to 2.5 kV.
Attention, connectors are not isolated from
each other!
Figure 40: Version with RS232-RS485/422 interface
Connection of RS232 connector:
Pin
Signal
Description
Direction
1
CTS
Clear To Send
Output
2
RTS
Request To Send
Input
3
GND
Signal ground
∗
—
4
RXD
Receive Data
Input
5
TXD
Transmit Data
Output
Table 19: Connection of RS232 connector
∗
Both connectors (RS232 and RS485/422) have common ground.
Figure 41: RS232 connector
Connection of RS485 connector:
Pin
Signal
Description
Direction
1
TxRx+
RS485 B (+)
Input/Output
2
TxRx-
RS485 A (-)
Input/Output
3
TxRx+
RS485 B (+)
Input/Output
4
TxRx-
RS485 A (-)
Input/Output
Table 20: Connection of RS485 connector
26