EN
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5.9 Grid output connection (AC side)
WARNING –
B
To avoid risks of electrical shock, all wiring operations must be carried out with the disconnect switch downstream of
the inverter (grid side) opened and applying LOTO procedure on it. Be careful not to mistakenly exchange the phases with neutral!
The inverter must be connected to a three-phase TN system with the center of the star connected to ground. To connect the inverter to the
grid is necessary to use a 3/4 wires connection (3 phases with or without neutral cable).
ATTENTION –
A
In case of PVS-100/120 GROUNDING KIT is installed on the inverter, it is mandatory the use of IT system without
connection of the center of the star to the ground.
ATTENTION –
A
In any case, the inverter’s earth connection is mandatory
The connections can also be made with the wiring box detached from the power module which can be connected later for commissioning.
ATTENTION –
A
When working with the wiring box detached, (pay particular attention to outdoor installations) always protect the top
of wiring box with proper IP66 protection covers (optional accessory content in the “PVS Installation KIT”, to be ordered separately)
on the housing. Refer to the dedicated
“Installations of IP66 protection covers for wiring box openings”
paragraph for further
information about the installation procedure.
5.9.1 Characteristics and sizing of the protective grounding cable
FIMER inverters must be earthed via the connection points marked with the protective earth symbol and using a cable with an
appropriate conductor cross-section for the maximum ground fault current that the generating system might experience.
According to IEC 62109-1:
If the external Protective earthing conductor cross-section area is S/2, where S is the cross-section of the phase conductor, no further
calculation are needed to demonstrate that the cross-section is enough to sustain the fault current. Otherwise the protective earthing
conductor cross-section shall be determined by calculation according to IEC 60364-5-54 or have to fulfill the requirement of local standard.
ATTENTION –
A
Any failure of the inverter when it is not connected to earth through the appropriate connection point is not covered
by the warranty.
The earth connection can be made through the Protective earth point (int.)
(25)
, Protective earth point (ext.)
(10)
or both (this is required
by regulations in force in certain countries of installation).
The sizing of the ground cable depend on the choice of the protective earth point (internal
(25)
or external
(10)
) where it will be connected:
Protective earth point (int.) (25)
Protective earth point (ext.) (10)
Cable diameter range
10 - 17 mm (M25 cable gland)
-
Conductor cross section
35...95 mm² (copper)
-
Cable lug dimensioning
b
a
for M10 Stud
a = 10.5 mm (min)
b = 40 mm (max)
for M8 Bolt
a = 8.4 mm (min) - 8.5 mm (max)
b = all dimension accepted
5.9.2 Load protection breaker (AC disconnect switch)
To protect the AC connection line of the inverter, an overcurrent protection device with the following features must be installed (these are
the caracteristic of a load protection switch referred to a single inverter installation):
Load protection breaker
PVS-100-TL
PVS-120-TL
PVS-100-TL
PVS-120-TL
Type
Automatic circuit breaker with thermal-
magnetic protection
Fuses switch disconnector
Voltage/current rating
400Vac
min.150A (*)
480Vac
min.150A (*)
400Vac
200A (*)
480Vac
200A (*)
Magnetic protection characteristic
Magnetic curve B/C
gG, gS
Number of poles
3/4
3/4
(*): please consider thermal and other derating when selecting the current rating of the protection equipment for your application.
