SMA America, LLC
Electrical Connection
Technical Description
SI5048U-TUS121440
53
1. Pierce the appropriate place on the cable insert with a pointed object.
2. Starting from the outside, feed the cables with bootlace ferrules through the hole in the Sunny
Island.
3. Connect the cables correspondingly to the ”BatCur” connection of the 4-pole print terminal
included in the delivery.
4. Tighten the terminals (torque: 5 in‑lbs. ‑ 7 in‑lbs. (0.56 Nm ‑ 0.79 Nm)).
5. Insert the 4-pole print terminal into the ”BatCur” socket on the Sunny Island.
☑ The battery current sensor is installed.
6.4.3 Communication for Multi-device Connection
The Sunny Island can be connected in parallel, split-phase or in a 3-phase system with other Sunny
Island devices in order to increase the overall power. The devices communicate with each other
through an RJ45 communication cable. A black RJ45 cable is provided with each Sunny Island. You
need the cable in order to establish an (internal) communication between several Sunny Island
devices. The maximum total length of the communication bus may
not
exceed 98 ft. (30 m). If you
operate only one Sunny Island in your system, the cable is not required.
Proceed as follows to implement the connection:
1. Remove one of the two plugs from the cable insert.
2. Feed the RJ45 cable from the outside through the plugs inside the Sunny Island master.
3. Remove the terminating resistor from the ”ComSyncOut” socket of the master and plug it into
the ”CompSyncIn” socket of the master.
4. Plug the RJ45 cable into the ”ComSyncOut” socket.
Use Cables of Intrinsically Safe Circuits
Use cables of intrinsically safe circuits for the connection of battery current sensors.
”Intrinsically safe” means here that the cable is double-insulated and that the wire melts but
the insulation remains intact in the event of a short-circuit. In addition, the cable is not
combustible. In order to avoid measuring errors, make sure to use twisted cables.
Installation Information
The battery current sensor must be looped around the negative pole of the battery. In
addition, the contact of that battery current sensor which is connected to the Sunny Island
(1) must be connected to the terminal ”” (see following figure).
• Positive battery current means that the battery is discharging (current from the
battery).
• Negative battery current means that the battery is charging (current into the battery).
Commissioning the Battery Temperature Sensor
When connecting a battery current sensor to the Sunny Island, the device's internal offset
must be adjusted during the first commissioning of the off-grid power system. To do this,
proceed as described in section 8.3 ”Connecting the Battery Current Sensor” (page 70).
