SMA HM-BT-10.GR2 - Information and System Description; Requirements of the VDE Forum Network Technology; Network Operations (FNN)

3 Information and System Description SMA Solar Technology AG
10 FSS-IS-en-42 Installation Manual - Quick Reference Guide
3 Information and System Description
3.1 Requirements of the "VDE Forum Network Technology / Network
Operations (FNN)"
The information below only applies for systems for which the following properties are all applicable:
• Only one Sunny Island is connected in the system.
• The grid operator requires compliance with the Technical Information "Connection and Operation of Storage Units"
of the FNN. Currently, only the grid operators in Germany require compliance with the above-mentioned Technical
Information (status: June 2014).
In these systems, the Sunny Island must be connected to a line conductor supplied by a single-phase PV inverter. If there
are only three-phase PV inverters connected in the system, the Sunny Island can be connected to any line conductor.
The requirements of the Technical Information "Connection and Operation of Storage Units in Low-Voltage Networks"
published by the FNN influence the discharge behavior of the Sunny Island inverter. In systems with one Sunny Island
and single-phase PV inverters, the SMA Flexible Storage System reduces the maximum discharge power of the
Sunny Island inverter as required.
Example 1:
All PV inverters are single-phase and are feeding in asymmetrically
(Sunny Boy). The PV inverters are connected to one line conductor.
The Sunny Island must be connected to the line conductor
into which the PV inverters are feeding.
Example 2:
All PV inverters are single-phase and are feeding in asymmetrically
(Sunny Boy). PV inverters are connected to two line conductors.
The Sunny Island must be connected to a line conductor into
which a single-phase PV inverter is feeding. TIP: Connect the
Sunny Island to the line conductor being supplied with the
least PV energy. This will increase the control range for
increased self-consumption.
Example 3:
All PV inverters are single-phase and are feeding in asymmetrically
(Sunny Boy). One PV inverter is connected to each line conductor.
The Sunny Island can be connected to any line conductor.
TIP: Connect the Sunny Island to the line conductor being
supplied with the least PV energy. This will increase the
control range for increased self-consumption.