SMA Solar Technology AG
Communication connector
Technical Description
SSMUS-TUS094511
29
6 Communication connector
• The communication between the Sunny Central String-Monitors and the Sunny Central is
provided using a RS485.
• The Sunny Central String-Monitors are connected to the Sunny Central within a bus (in series).
• The bus may not be longer than 4,000 ft (1,200 m) in total.
• Connection of up to 4 hubs for the connection of 4 buses possible (see section
11.2 "Communication Overview" (page 61)).
• The last Sunny Central String-Monitor in the bus and the Sunny Central must be terminated (see
section 6.2.3 "Terminate the RS485 bus in the Sunny Central String-Monitor" (page 34) and
section 7 "Electrical Connection" (page 37)).
Data cable
Use a shielded twisted pair data cable with a cross-
section of 2 x 2 x AWG 24.
A
Flexible PVC insulation
B
Shielding (copper shielding braid)
C
Twisted Pair 1 (2 x AWG 24)
D
Twisted Pair 2 (2 x AWG 24)
Recommendation data cable
SMA also provides communication cables. Please contact your installer or wholesaler.
RS485
RS485
RS485
4,000 ft
1
2
3
4
A
B
C
D
