SMA SI 4548-US - Manual (Page 49)

SMA America, LLC 6 Electrical Connection
Operating Manual SI4548-6048-US-BE-en-20 49
Connecting the AC1 cable:
1. Install a conduit with a diameter of
3
/
4
in. (19 mm) at the left opening on the left side of the
Sunny Island enclosure. Attach the conduit on the inside of the Sunny Island with a counter nut.
2. Install the conduit on the distribution board.
3. Pull the cable from the distribution board through the conduit into the Sunny Island.
4. Remove the protective insulation of the three cables (insulation stripping length: 0.75 in
(18 mm)).
5. Insert the grounding conductor into the terminal labeled "AC1 Loads/Sunny Boys" and tighten
the fastening screw with a torque of 22 in-lb (2.5 Nm). Use a torque wrench with flat-blade
screwdriver bit SZS 1.0 x 6.5.
Double-split-phase system
In a double split-phase system, connect the master and slave 2 to line conductor L1.
In a double split-phase system, connect slave 1 and slave 3 to line conductor L2.
Connection in a three-phase system
Always install the master on line conductor L1, slave 1 on L2 and slave 2 on L3. This installation
has a right-hand rotating magnetic field.
Failure of a line conductor within a three-phase system
If in a three-phase system, a line conductor fails on the master, the cluster stops. If a line
conductor fails on a slave, the cluster can either continue to operate or switch off. Whether the
cluster continues to work or switches off depends on the setting of the parameter "250.30
RnMod" (see Section 19.2.5 "System Settings (250#)", page 190).
Wire size
The maximum wire size for connecting the loads/PV inverters is 4 AWG (25 mm²).