SMA DB-DC-DISCON - Manual (Page 3)

SMA Solar Technology AG
DC_Disc-IUS082311 3 / 4 Additional Information for Installation
DC Wiring With Additional DC Distribution
When combining strings outside of the SMA DC-Disconnect, and when the combined input of a sin-
gle source circuit is greater than 15 A, use the terminal labeled COMBINED for the ungrounded
conductor. DO NOT use the terminals 1 - 4 labeled UNGROUNDED in this case.
Pay attention to all operation and safety instructions listed in the Installation Guide of the Sunny Boy.
This instruction does NOT replace the Sunny Boy Installation Guide.
For connecting the DC wires to the Sunny Boy, see Installation Guide of the Sunny Boy.
Torque Values and Wire Sizes SMA DC-Disconnect
Additional DC Source Circuit
Note: This circuit will no longer be fused so additional DC source circuit fusing may be
required in order to meet UL and NEC.
Negative Grounding
Connect the positive DC wire to the terminal la-
beled COMBINED in the SMA DC-Disconnect.
Connect the negative DC wire to the terminal la-
beled PV GROUNDED in the SMA DC-Discon-
nect.
Positive Grounding
Connect the negative DC wire to the terminal la-
beled COMBINED in the SMA DC-Disconnect.
Connect the positive DC wire to the terminal la-
beled PV GROUNDED in the SMA DC-Discon-
nect.
Terminal in-lbs Nm. Wire Size
AC & DC Terminal Blocks 15 1.7 6 - 10 AWG
Combined Terminal Block Spring Terminal Spring Terminal 6 - 10 AWG
Grounding Electrode Conductor Block 15 1.7 6 - 10 AWG