Sunny Island
Installation & Operating Instructions
BWRI33-12:EE
- 45 -
SMA Regelsysteme GmbH
3.6.2 Assignment of COM2 Interface
The signals listed in Table 3.3 are available when the corresponding Piggy-Back has
been installed.
PIN
RS485 Signal
RS232 Signal
1
2
Data +
/RXD (Input of Sunny Island)
3
Data +
/TXD (Output of Sunny Island)
4
DTR (Output of Sunny Island)
5 GND
GND
6
+5V
DSR (Input of Sunny Island)
7
RTS (Output of Sunny Island)
8
Data -
CTS (Input of Sunny Island)
9 Data
-
Table 3.3: Assignment of COM2 interface (RS485 / RS232)
Recommended cable for RS485 (COM1 and COM2)
We generally recommend a so-called LICY 2 x 2 x 0.25 mm² cable as shown in Fig.
3.19.
1
2
3
4
Flexible PVC
insulation
Shielding
Twisted pair 2 (2 x 0.25 mm)
Twisted pair 1 (2 x 0.25 mm)
Fig. 3.19: Recommended cable for RS485 communication
The total length of the RS485 connection cable may not exceed 1200 m.
