INSTALLATION GUIDE
MODULAR SUNWAY TG
TE OD
Rev. 03
– 01/06/2018
73/
139
If a measurement VT is to be connected to the AC output phases of the SUNWAY TG TE inverter, earthing
the transformer windings is forbidden.
The VT impedance is guaranteed at grid frequency only. Common mode currents at switching frequency
are present in the plant and might affect the VT. In case of earth fault occurring in the PV field, not-null
average currents may flow in the low-impedance VT windings to ground. Those currents might quickly
saturate the VT cores and damage them.
Adopt the following configuration to connect the VT to the inverter AC output:
•
Delta configuration.
•
Star configuration referred to the neutral (use the neutral obtained from the star centre of the LV/MV
transformer).
It is advisable to use VTs with isolation voltage to earth of at least 2500 V
AC
/50 Hz/60s for the 1000V version
and 3000 V
AC
/50 Hz/60s for the 1500V version.
6.9.
Reassembling the protective grilles
The figure below shows the safety grilles that have been reassembled (see Figure 43).
Figure 43: Protective grilles reassembled
6.10.
Commissioning
This chapter deals with the essential procedures involved in equipment commissioning.
DANGER
Do not apply power to the product if the internal protective grilles have been removed.
Always carry out the operations described in section 6.9 before starting up the inverter.
WARNING
Wire the inverter in accordance with the instructions given in the sections above before
starting the inverter.
Checks:
