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001048AG
3 - Characteristics
S
afety devices
A
nti-Islanding
In the event of a local grid outage by the electricity company, or when
the equipment is switched off for maintenance operations, the inverter
must be physically disconnected to ensure the protection of the people
working on the grid, in accordance with the relevant national laws and
regulations. To prevent possible islanding, the inverter is equipped with
an automatic safety disconnection system called “Anti-Islanding”.
The method used to ensure an active anti-islanding protection is: active
frequency drift in combination with RoCoF techniques.
Anti-islanding protection mechanisms are different depending on the grid
standards, even if they all have the same purpose.
G
round fault of the photovoltaic panels
Use this inverter with panels connected in "floating" mode, i.e. with no
earth connections on the positive and negative terminals. An advanced
ground fault protection circuit continuously monitors the ground connection
and disconnects the inverter when a ground fault indicating the fault con-
dition by means of the red "GFI" LED on the LED panel
on the front side
of wiring box.
S
tring fuses
The DC compartment can be equipped with string fuses are:
-S version - Negative side (-) string fuses
34
and the positive side (+) string
fuses
35
are preinstalled.
-SC version - Negative side (-) string fuses
34
and the positive side (+)
string fuses
35
are preinstalled.
The fuses protect the appliance from currents exceeding the limit value
independently for each string.
The sizing of the fuses must therefore be carefully assessed during in-
stallation.
O
vervoltage surge arresters
As an additional protection to prevent damage caused by the discharges
from lightning and electrostatic induction phenomena, the wiring box is
equipped with DC overvoltage surge arresters
32
and with AC overvoltage
surge arresters
36
.
O
ther safeguards
The inverter is equipped with additional protective devices to ensure safe
operation in any circumstance. These protections include:
- Constant monitoring of the grid voltage to ensure that voltage and fre-
quency values remain within operating limits;
- Internal temperature control to automatically limit the power if necessary to
prevent overheating of the unit (derating).
The numerous control systems determine a redundant structure to ensu-
re absolutely safe operations.
