SMA SUNNY ISLAND 6.0H Quick Reference Manual page 8

2 Safety
• Battery-backup system with all-pole disconnection
In the event of grid failure, a tie switch disconnects all line conductors and the neutral conductor from the utility
grid. If the technical connection requirements of the grid operator or the local standards and directives call for or
allow all-pole disconnection, you must install this basic structure, e.g. in Belgium, Denmark, Germany, Austria and
Switzerland.
• Battery-backup system without all-pole disconnection
In the event of grid failure, a tie switch disconnects all line conductors from the utility grid. The neutral conductor of
the battery-backup grid remains permanently connected to the utility grid. If the technical connection requirements
of the grid operator or the local standards and directives prohibit disconnection of the neutral conductor, you must
install this basic structure.
Single-phase clusters are not permitted. Only Sunny Island inverters of the same device type may be installed in a
three-phase cluster. Several clusters may only be interconnected if the Multicluster-Box 12 (MC-BOX-12.3-20) is used
for it.
Single-phase battery-backup grids can be connected to three-phase utility grids. In a single-phase battery-backup
system, a grid failure is only recognized at the line conductor that is connected to the Sunny Island. In the event of grid
failure, only single-phase PV inverters can feed into a single-phase battery-backup grid.
The connected PV inverters must be suitable for use in battery-backup systems. In addition, the power of the PV system
must be appropriate for the system (see planning guidelines "SMA Flexible Storage System with Battery Backup
Function" at www.SMA-Solar.com).
In a three-phase battery-backup system, both single-phase and three-phase PV inverters can be connected.
The battery-backup system must be equipped with an automatic transfer switch (see planning guidelines
"SMA Flexible Storage System with Battery Backup Function" at www.SMA-Solar.com). This automatic transfer switch
is not part of the Sunny Island scope of delivery.
The automatic transfer switch is not a distribution board for the loads or the PV system. The loads and the PV system
must be secured with protective devices in accordance with the local standards and directives. Grid-forming voltage
sources (e.g. generators) must not be connected to the battery-backup system. The equipment or devices of the
automatic transfer switch must satisfy protection class II and be operable without prior knowledge of electrical
engineering.
The tie switch in the automatic transfer switch must have an ampacity that is designed for at least the operating range
of the upstream fuse.
Grid feed-in and purchased electricity are recorded with an SMA Energy Meter only. An SMA Energy Meter does not
replace the energy meter of the electric utility company.
2.2 IMPORTANT SAFETY INSTRUCTIONS
This section contains safety information that must be observed at all times when working on or with the product.
To prevent personal injury and property damage and to ensure long-term operation of the product, read this section
carefully and observe all safety information at all times.
8 SI44M-60H-80H-12-IS-xx-12
SMA Solar Technology AG
Quick Reference Guide