Electrical connection SMA America, LLC
58 SB30-40US-IUS103030 Installation Guide
Jumper configuration for RS485 communication
RS485 pinouts
2 - A (+) (Data+)
7 - B ( − ) (Data − )
5 - SR (Signal Ref.)
Jumpers B and C Installed: Installing these jumpers puts 680 Ohm symmetry resistors between
pin 2 (Data+) and +5V and between pin 7 (Data − ) and Ground.
Jumper A installed: Installing this jumper puts a 120 Ohm termination resistor across
pin 2 (Data+)and pin 7 (Data − ).
• Install jumper A only, if the inverter is on one of the ends of the RS485 bus.
• Install jumpers B and C only:
– After the inverter is on the RS485 bus.
– Only if symmetry of the signal is required.
Symmetry is already provided by the Sunny Boy Control and Sunny WebBox products.
RS485 Piggy-Back
Communication Module
Signal Symmetry and
Termination Jumpers
Terminal Block for
RS-485 Connection