SMA SUNNY BOY 3.0-US Instructions D'installation page 20

4 Product Overview
CONTROLLED CONDUCTORS OUTSIDE THE ARRAY. OTHER EQUIPMENT INSTALLED IN OR
ON THIS PV SYSTEM MAY ADVERSLY AFFECT THE OPERATION OF THE PV RAPID SHUTDOWN
SYSTEM. IT IS THE RESPONSIBILITY OF THE INSTALLER TO ENSURE THAT THE COMPLETED PV
SYSTEM MEETS THE RAPID SHUT DOWN FUNCTIONAL REQUIREMENTS. THIS EQUIPMENT
MUST BE INSTALLED ACCORDING TO THE MANUFACTURER'S INSTALLATION MANUAL.
Parallel Operation of the DC Inputs A and B
The DC inputs A and B of the inverter can be operated in parallel and up to three strings can be
connected to it in parallel. As a result, as opposed to normal operation, up to three strings can be
connected directly to inverters with two DC inputs and up to four strings to inverters with three DC
inputs. The inverter automatically detects the parallel operation of the DC inputs A and B.
Secure power supply operation
You can connect an external outlet and a switch to the inverter in order to enable the outlet. In case
of a grid failure, the outlet supplies a load with current from the PV system. When the outlet is
enabled via the switch, the load is supplied with current from the PV system. The inverter
automatically regulates the energy supply of the outlet depending on the solar irradiation on the PV
system. When the outlet is enabled and a load is supplied with current from the PV system, the
inverter is disconnected from the utility grid and does not feed into the utility grid.
Do not connect loads that require a stable electricity supply to the outlet for
secure power supply operation.
Secure power supply operation must not be used for loads that require a stable electricity
supply. The power available during secure power supply operation depends on the solar
irradiation on the PV system. Therefore, power output can fluctuate considerably depending
on the weather or may not be available at all.
• Do not connect loads to the outlet for secure power supply operation if they are
dependent on a stable electricity supply for reliable operation.
Multifunction Relay
The inverter is equipped with a multifunction relay as standard. The multifunction relay is an
interface that can be configured for the operating mode used by a particular system.
SMA ShadeFix
The inverter is equipped with the shade management system SMA ShadeFix. SMA ShadeFix uses
an intelligent MPP tracking system to determine the operating point with the highest output during
shading conditions. With SMA ShadeFix, inverters use the best possible energy supply from the PV
modules at all times to increase yields in shaded systems. SMA ShadeFix is enabled by default. The
time interval of SMA ShadeFix is usually six minutes. This means that the inverter determines the
optimum operating point every six minutes. Depending on the PV system or shading situation, it may
be useful to adjust the time interval.
String-failure detection
The self-learning string failure detection identifies to which of the three inverter DC inputs the strings
are connected. The self-learning string failure detection identifies if the connected string is
inoperable and is no longer contributing to the energy yield (e.g. due to damages such as a cable
break) and monitors the input to which the defective string is connected. If the error persists, an
20 SBxx-1SP-US-41-IA-xx-12
SMA Solar Technology AG
Installation Manual