Elektro-Automatik ELR 9000 Betriebsanleitung Seite 127

2.3.4.3 Connecting multiple units to one supply
When connecting more than one unit to the same supply point, ideally models with the same nominal power, it is
recommended to take care for balanced current distribution on the phases. This can be achieved by considering
the single phase current of the particular models and by varying the supply phases you connect to the AC plug.
Because the table above says "use phases L2 and L3 to power a 3.1 kW model", even multiple units with this power
would be intentionally connected to L2 and L3, while not using L1. With the 7 kW it's different, because the shared
phases have a higher current. A fully balanced current can be achieved when having three units or a multiple of
3, while with an even number of units the current can be only distributed as good as possible by connecting the
units to different phases. See examples below.
L1
ELR 3.1kW
L2
Unit 1
L3
L1 L1
ELR 3.1kW
L2 L2
Unit 2
L3 L3
L1
ELR 3.1kW
L2
Unit 3
L3
Figure 10 - Example for AC wiring of multiple 3.1 kW units
2.3.4.4 Installation concept for energy recovering devices
The 3.5 kW models are rated for max. 16 A current and could be connected to a standard 16 A wall socket or even
a multi-outlet strip. We strongly disadvise doing so, because the recovered current adds to the grid current (see
schematic below) and this can lead to overload of the existing installation. Considering any two outlets, no matter
of what kind they are, but especially when being wall sockets, there is usually no extra fusing installed. In case of
a defect in the AC part (i.e. short-circuit) of any consumer device or if there are multiple devices connected which
could take a higher power, the total current could flow across wires which are not laid out for this higher current .
It could lead to damage or even fire in the wires or connection points.
This applies the same way for all other ELR 9000 power ratings.
The existing installation concept must be taken into regard when connecting further ELR 9000 units and consum-
ers in order to avoid damages and accidents. Schematic depiction with 1 recovering load:
16 A
Grid
ELR 9000
When running a higher number of recovering, i. e. energy backfeeding units on the same leg of the installation,
the total currents per phase increases accordingly.
EA Elektro-Automatik GmbH
Helmholtzstr. 31-33 • 41747 Viersen
Germany
L1 L2 L3
(A) (B) (C)
up to 32 A
16 A
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
L1
ELR 6.2kW
L2
Unit 1
L3
L1
ELR 6.2kW
L2
Unit 2
L3
L1
ELR 6.2kW
L2
Unit 3
L3
Figure 11 - Example for AC wiring of multiple 6.2 kW units
Consumer 1
Consumer 2
www.elektroautomatik.de
ea1974@elektroautomatik.de
ELR 9000 Series
L1 L2 L3
(A) (B) (C)
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