General Recommendations; Specifications - ABB REACT-3.6-TL Application Note

The backup output can support household loads (e.i. A refrigerator, a freezer, heat pumps, hoovers, etc.) and
electronic devices that comply with the specifications shown in Chapter 4.
3.

General recommendations

The backup output must be considered as a source of power completely independent on the electric grid of the local
distributor, which provides dedicated loads or priority loads as defined in the previous section, so it must be sized and
designed in a workmanlike manner in compliance with the applicable legislation in force in the place where the
system is installed (see Chapter 4). All the utilities fed by the backup line will be supported as long as the energy from
the photovoltaic field and the energy accumulated in the battery will be sufficient to meet the demand of connected
users.
Furthermore, we point out that the backup function should not be considered as an emergency function, but rather as
an uninterruptible power supply (UPS) system installed to provide constant power to the equipment connected, even
in case of network malfunction. If, and only if, the automatic mode is set (see Chapter 5), the backup output can be
activated in about two minutes after a network fault to provide power to the utilities connected.
For safety reasons, it is mandatory to appropriately identify the electric sockets connected to the backup line, since
they could be powered even if there is no network connection. For this reason, all the sockets connected to the
backup output should be marked with an identification tag, with indication, in the main switchboard, of the presence
of an alternative source of power to the distributor's grid.
So, as for the systems where emergency/UPS systems are installed, the presence of any dangerous voltage in the
circuit must be indicated to prevent risks in case of actions and operations on the electric system. We recommend
using warning methods like the one shown in the figure:
In the backup operating mode, the system automatically connects the neutral conductor of the earth line, this
ensuring a correct operation of the dedicated differential protection.
4.

Specifications

The backup output is a single-phase AC voltage supply made available by the inverter, which must be sized like any
single-phase line. The following section provides the specifications of the output and indications on how to size the
connected line.
The backup output is accessible through the AC-1 connector available on the REACT-UNO inverter by wiring the BACK-
UP terminal block in the machine, which can be reached after disconnecting the machine (consult the manual for the
procedure) by removing the front panel of the inverter, as shown in the figure:
Application Note| REACT-3.6/4.6-TL – BACKUP OUTPUT|Operation and Configuration 4