Notes For The Installer; Transformers - Aros SIRIO EVO Serie Manual De Instalacion Y Uso

N
OTES FOR THE INSTALLER
T
RANSFORMERS
The inverter has been designed to work with LV type TT, TN or TN-S grids.
If the inverter is connected to other types of grid, for example IT grids, contact the manufacturer to check feasibility in the specific
case.
If it should be necessary to use an isolation transformer between inverter/s and the grid, connect the local neutral point of the
transformer to the grounding to ensure inverter operation with the correct distribution systems (TN or TT as previously
mentioned).
See the examples in the table below. The numbers shown have the following meaning:
1. No reference point to the neutral grounding: IT system.
2. Galvanic isolation has been violated and measurement errors introduced in the inverter
3. No connection to the neutral point of transformer on the grid side. The three star voltages on the inverter side vary quite
a bit based on the power fed on each phase.
In the event of single phase transformer use, the wiring side connected to the grounding becomes neutral.
Wrong connection
3P+N
3P+N
3P+N
3P+N
3P+N
N
P+N
P+N
Reason for error
1
3P
GRID
1
3P+N
GRID
3P+N
2
GRID
3P+N
2
GRID
3
3P
GRID
P+N
2
GRID
1
P+N
GRID
- 62 -
Correct connection
3P+N 3P
N
3P+N 3P+N
N
3P+N 3P+N
N
3P+N 3P
N
3P+N 3P+N
N
P+N P+N
N
P+N P+N
N
GRID
GRID
GRID
GRID
GRID
GRID
GRID