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Liabilities arising from commercial components are delegated to their respective manufacturers.
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Any time the inverter has been disconnected from the public network, please be extremely
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cautious as some components can retain charge sufficient to create a shock hazard. Prior to
touching any part of the inverter please ensure surfaces and equipment are under touch safe
temperatures and voltage potentials before proceeding.
This product was not tested to section 5 of AS/NZS 4777.2:2020, and is not to be used in multi
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ple inverter combinations without addtional measures taken within the installation to ensure
continued compliance to requirements.
If the inverter are not connected to the internet, the inverter should be installed in a high traffic
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area where the alarm would be noticed, or an external Earth Fault Alarm should be installed.
2.2 PE Connection and Leakage Current
PV System Residual Current Factors
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In every PV installation, several elements contribute to the current leakage to protective earth (PE).
these elements can be divided into two main types.
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Capacitive discharge current - Discharge current is generated mainly by the parasitic capacitance of
the PV modules to PE. The module type, the environmental conditions (rain, humidity) and even the
distance of the modules from the roof can effect the discharge current. Other factors that may
contribute to the parasitic capacitance are the inverter's internal capacitance to PE and external
protection elements such as lighting protection.
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During operation, the DC bus is connected to the alternating current grid via the inverter. Thus, a
portion of the alternating voltage amplitude arrives at the DC bus. The fluctuating voltage constantly
changes the charge state of the parasitic PV capacitor (i.e capacitance to PE). This is associated
with a displacement current, which is proportional to the capacitance and the applied voltage
amplitude.
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Residual current - if there is a fault, such as defective insulation, where an energized cable comes
into contact with a grounded person, an additional current flows, known as a residual current.
Residual Current Device (RCD)
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All Energizer Solar inverters incorporate a certified internal RCD (Residual Current Device) to protect
against possible electrocution in case of a malfunction of the PV array, cables or inverter (DC). The
RCD in the Energizer Solar inverter can detect leakage on the DC side. There are 2 trip thresholds
for the RCD as required by the DIN VDE 0126-1-1 standard. A low threshold is used to protect against
rapid changes in leakage typical of direct contact by people. A higher threshold is used for slowly
rising leakage currents, to limit the current in grounding conductors for the safety. The default value
for higher speed personal protection is 30mA, and 300mA per unit for lower speed fire safety.
Installation and Selection of an External RCD device
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An external RCD is required in some countries. The installer must check which type of RCD is
required by the specific local electric codes. Installation of an RCD must always be conducted in
accordance with local codes and standards. Energizer Solar recommends the use of a type-A RCD.
Unless a lower value is required by the specific local electric codes, Energizer Solar suggests an
RCD value between 100mA and 300mA.
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In installations where the local electric code requires an RCD with a lower leakage setting, the
discharge current might result in nuisance tripping of the external RCD. The following steps are
recommended to avoid nuisance tripping of the external RCD:
1. Selecting the appropriate RCD is important for correct operation of the installation. An RCD with a rating
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