Auxiliary Transformer - Ingecon Sun 250 M220 Indoor Installation Manual

Installation manual
Because of inverter operation, the voltage between a phase and ground can reach 3/2 of the open circuit voltage
of the PV array.
7. We recommend using the Dy11 connection.
8. The neutral of the low voltage winding must not be grounded.
9. The connection to the medium voltage network will be the nominal connection point.
10. We advise using transformers equipped with five-point voltage regulators, with the possibility of selecting
the following options:
no electronic equipment may be connected to the power grid. All auxiliary loads must be isolated from the power grid
through a transformer with galvanic isolation.

5.3.2. Auxiliary transformer

The auxiliary transformer transforms the voltage from the power part of the unit to its control and consumption part.
Ingecon
®
The primary circuit is connected to the power input. We recommend installing protection and switching components
to protect this transformer.
The technical requirements of the auxiliary transformer are:
1. The transformer's power should be suitable for the loads connected to it. Take into account the environ-
mental conditions of the site.
2. The power winding must withstand pulsating voltage components with du/dt of 500 V/uS. Because of
inverter operation, the voltage between a phase and ground can reach 3/2 of the open circuit voltage of the PV
array.
3. Delta connection is advised in the power part and star connection in auxiliary loads. We advise connecting
the neutral of auxiliary loads to ground.
AAV2000IKI01
5% 2.5%
Sun Power Max
Auxiliary loads
0% -2.5% -5%
P
Auxiliary protections
Ingeteam
S
37