SMA Solar Technology AG
Installation Guide
SB50US-80US-IUS094030
47
5.5.2 AC Wiring Without SMA DC-Disconnect
Use the following procedure to connect the AC wires to the Sunny Boy without the SMA DC-
Disconnect:
1. Turn OFF the main breaker in the main utility breaker box.
2. Remove interior breaker panel cover.
3. If you are replacing an existing inverter, disconnect the wires for the AC line you are working
with in the breaker box.
4. Install a 3/4-inch conduit fitting in the Sunny Boy’s AC wiring knockout (the knockout on the right
side of the Sunny Boy, as shown in chapter 5.2 "Bottom View and Dimensions" (page 40)).
Fasten the conduit fitting on the inside of the Sunny Boy with the appropriate locknut.
5. Install a 3/4-inch conduit between the main breaker box and the Sunny Boy’s AC wiring
knockout.
6. Pull the AC wires through the conduit from the interior of the breaker box to the interior of the
Sunny Boy.
7. Refer to the figures on pages 48 and 49 for steps 8 through 10.
8. Connect the AC equipment-ground wire to the PE terminal labeled
in the Sunny Boy.
9. For 208/240/277 V connect the L1 (AC line 1 or UNGROUNDED) wire to the terminal
labeled L1 in the Sunny Boy.
10. For 208/240 V connect the L2 (AC line 2) and N (AC line N) wire to the terminal labeled L2
and N in the Sunny Boy. For 277 V connect the N (AC line N) wire to the terminal labeled N
in the Sunny Boy.
Note: For 277 V the L2 terminal is not used.
WARNING!
You must connect the wires that carry the AC voltage from the Sunny Boy to the utility grid
in the order described in this procedure. Deviating from this procedure could expose you
to lethal voltages that can cause serious injury and/or death.
CAUTION!
Avoid using wire nuts to join any wires together or to make any connections anywhere in
the PV system. Wire nuts are a frequent cause of unreliable, resistive connections, and
ground faults.
The Sunny Boy 8000US may not be connected to a 208 V grid.
