SMA SI 3.0-11 Installation - Manual (Page 27)

SMA Solar Technology AG 7 Electrical Connection
Installation Manual SI30M-44M-60H-80H-IA-en-30 27
7.4 Connecting the Devices
7.4.1 Connecting the Fuse Switch-Disconnector BatFuse to the Sunny Island
Procedure:
1. Ensure that the load-break switch of the BatFuse is open and secured against reconnection.
2. On the Sunny Island, remove all screws of the lower enclosure lid using an Allen key (AF 5) and remove the
enclosure lid. Retain the screws and conical spring washers for later use.
3. Clean the contact surfaces of the DC+ and DC- connections with ethanol, for example. This reduces the transition
resistance on the contact surfaces. A low transition resistance increases the system stability and minimizes the risk of
damage to the Sunny Island.
Cables for DC connection
Long cables and insufficient conductor cross-sections reduce the efficiency of the system and the overload capacity
of the Sunny Island inverter. The maximum cable length from the battery to the Sunny Island via the fuse
switch-disconnector is 10 m. The recommended minimum conductor cross-section is dependent upon the battery
voltage, power, and cable length:
Sunny Island Cable length*
* Cable length from the battery to the Sunny Island via the fuse switch-disconnector
Conductor
cross-section
Cable diameter**
** Maximum cable diameter on the Sunny Island: 25 mm Maximum cable diameter on the BatFuse: 21 mm
Terminal lug
SI 8.0H ≤ 5 m 70 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
>5 m 95 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
SI 6.0H ≤ 5 m 50 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
>5 m 70 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
SI 4.4M ≤ 5 m 50 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
>5 m 70 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
SI 3.0M ≤ 5 m 50 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
>5 m 70 mm² 14 mm to 21 mm M8, 20 mm to 25 mm wide
:$51,1*
Danger to life due to incompatible lithium-ion battery
An incompatible lithium-ion battery can lead to a fire or an explosion. With incompatible lithium-ion batteries, it is not
ensured that the battery management will protect the battery.
• Ensure that the battery complies with the locally applicable standards and directives and is intrinsically safe.
• Ensure that the lithium-ion batteries are approved for use with the Sunny Island.
The list of lithium-ion batteries approved for the Sunny Island is updated regularly (see the Technical Information
"List of Approved Lithium-Ion Batteries" at www.SMA-Solar.com).
• If no lithium-ion batteries approved for the Sunny Island can be used, use lead-acid batteries.