Installation
28 900-0111-01-00 Rev A
Parallel Stacking (Dual-Stack and Larger)
In parallel stacking, two or more inverters are stacked to create a single, common 230 Vac bus.
All inverters share a common input (AC source) and run loads on a common output.
Up to ten inverters may be installed in a parallel arrangement. The example on this page shows three
inverters. The wiring diagram on the next page shows four.
Figure 20 Example of Parallel Stacking Arrangement (Three Inverters)
When installing a parallel system, the following rules must be observed.
Parallel stacking requires a system display and a HUB.
The inverter that is mounted physically lowest is always the master and is programmed as
Master
. (See the
system display manual for programming.) Mounting below the other inverters allows the master to avoid
heat buildup and remain relatively cool, as it sees the greatest duty cycle.
The master must be connected to port 1 of the HUB. Other inverters must not be selected as master.
All slave inverters, regardless of quantity, should be selected as
OB Slave L1
during programming.
All inverter wiring and input breakers must be sized for 30 Aac or less.
All inverters must be of the same model.
The AC input (generator or utility grid) must be 230 Vac at 50 Hz (single-phase).
When wiring the AC source to the inverters, local codes may require the inverter breakers to be located at
the bottom of the main panel. This prevents overloading of the AC bus.
3.9 kVA
230 Vac
1.3 kVA 230 Vac
1.3 kVA 230 Vac
1.3 kVA 230 Vac
