8
External relay for the backup power supply
Connecting an external relay
Through use of an external relay, some of the single
phase loads can be connected to the AC LOCAL OUT
connection on the PowerRouter, which provides backup
power during a power outage. This creates a backup
system with a switch-over time of ≥ 1 second providing
the connected loads with an backup with a stable 230
VAC/50 Hz output. The power provided during a power
outage comes simultaneously from the solar energy
that is being generated at that moment and from the
batteries. It is important to note, however, that only
a portion of the loads can be supplied with backup
power, because the reserve capacity of a self-use
system is limited by the available solar energy and the
size of the battery bank.
A beneficial aspect of this switching configuration is
that loads draw power from the grid whenever the
PowerRouter is restarted or in standby.
The PowerRouter has two sets of configurable potential-free contacts. When a grid outage occurs, loads are
switched to backup power via an external relay. An advantage to this system is that there is no current flowing
through the relay coil during normal use. In addition, the PowerRouter controls the exact moment of switch-
over, which enables it to bring the current provided at AC LOCAL OUT into synch with the mains current as
the grid power is restored. Another advantage is that delay times can be configured, using the PowerRouter
Software Installation Tool*. This makes it possible to prevent the backup power provision from responding to
brief power interruptions (brown-outs).
*For more information about the settings, please consult the PowerRouter application guideline - Software Installation Tool, which you can
download from our website.
Technical data - external relay
The external relay can be any standard, commercially available relay with the technical specifications shown
below.
Europe except UK
UK
>
Coil voltage: 230 VAC
>
Coil voltage: 230 VAC
>
Contact ratings: 40 A for both N/O and N/C contacts
>
Contact ratings: 95 A for both N/O and N/C contacts
>
Contact configuration: 2 contacts, or 2 N/Os and 2 N/Cs
>
Contact configuration: 2 contacts, or 2 N/Os and 2 N/Cs
>
Contact gap: ≥ 3.2 mm
>
Contact gap: ≥ 3.2 mm
As indicated in the picture above, only single-phase consumers can be connected to AC LOCAL OUT. When
producing backup power, the PowerRouter generates its own AC output which cannot be synchronised with the
other two phases.
Figure 7: Connecting an external relay for backup power
0 1 7 7 6 3
0 1 7 7 6 3
t
u
o
l
a
c
o
l
C
A
d
ir
g
C
A
L3
N
L
NC
NO
N
L
L2
L1
N
L3
R1
R2
3
4
L2
L1
L
N
N
R7
R8
5
6
A1
A2
