SMA Off-Grid Systems - Manual (Page 19)

SMA Solar Technology AG 4 Single System
Installation - Quick Reference Guide Off-Grid-IS-en-30 19
4.3 Connecting RS485 to the Sunny WebBox
Figure 7: Connecting the RS485 communication bus to the Sunny WebBox
F Measuring cable of the
battery temperature sensor
Sunny Island: BatTmp terminal
You only have to connect a battery temperature sensor if lead-acid
batteries are used.
Mount the battery temperature sensor in the middle of the battery terminal,
in the upper third of the battery cell.
G Control cable, load
shedding
Sunny Island: Connect the control cable to the terminals Relay2 NO and
BatVtgOut − .
Inside the Sunny Island inverter, connect terminal Relay2 C and
BatVtgOut+.
Conductor cross-section: 0.2 mm² to 2.5 mm²
H RS485 communication bus Sunny Island: at SI-COMSMA.BGx terminal ComSmaOut
Connection to other nodes, e.g., PV inverter
A terminator must terminate the RS485 communication bus on the last bus
node.
I Data cable to
Sunny Remote Control
display
Sunny Island: Display terminal
K Data cable to Sunny Island
Charger
Sunny Island: ComSync In terminal
An additional data cable must be connected from the terminal
ComSync Out to the battery only when lithium-ion batteries are used.
The communication bus must be equipped with a terminator on both ends.
L RS485 communication bus Sunny Island: at SI-COMSMA.BGx terminal ComSmaIn
Sunny WebBox: terminal SMACOM
− Data cable to lithium-ion
battery
Only with lithium-ion batteries: additional data cable on terminal
ComSync In
Position Designation Description/information
A Jumper J1A Terminator
If the Sunny WebBox is installed at the end of the communication bus,
a jumper must be inserted.
If the Sunny WebBox is installed between two nodes, the jumper must be
removed.
B Jumper J1B and J1C Signal bias voltage
Make sure that both jumpers are inserted.
Position Designation Description/information