Application Note| REACT-3.6/4.6-TL – BACKUP OUTPUT|Operation and Configuration 6
BACKUP OUTPUT – Sizing of the line conductor
Conductor size (mm
2
)
Maximum length of conductor (m)
1.5
6
2.5
11
4
19
The values are determined in nominal power conditions by considering:
- max 1% loss of power along the line
- copper cable used with HEPR rubber insulation, laid in free air
The backup line must be protected by installing a device against maximum current and dispersion currents
characterised by the features below:
BACKUP OUTPUT – Dedicated under load protection
Type
Circuit breaker with differential magnetic-thermal protection
Voltage rating
230 Vac
Current rating
16 A
Magnetic protection charact.
B/C
Type of differential protection
A/AC
Differential sensitivity
30 mA
Number of poles
2
For differential protection, we suggest using the ABB
DS201C16
model.
5.
Operation modes
There are 6 modes that can be selected for the operation of the backup system. They can be set on the inverter's
display through the backup menu or through the web server inside the inverter.
The user/designer will select the most appropriate operation mode for the intended use of the system in the house or,
more generally, in the place where the system is installed.
These 6 operation modes are described below, with indication on how to enable and disable them for each input and
output of the backup system.
The types of work include 4 manual modes, that need an external manual input to be activated, and 2 automatic
modes, that are activated automatically depending on the state of external logics, such as a power failure or the state
of a dedicated control.
In the description of the various operation modes, the term “power failure” means the absence of voltage at the
output terminals of the inverter, a condition that can NOT coincide with the absence of voltage inside the house or in
the system in general.
We specify that the inverter will never be simultaneously operating in Grid Connected mode and Backup mode,
therefore the contactors connected to the AC GRID terminal block and to the BACKUP terminal block inside the
machine will never be simultaneously closed. The principle is that the inverter will switch between three different
states that exclude one another, as shown in the figure below:
