Selecting A Residual Current Device (Rcd) - SolarEdge SE8000H-AU Installation Manual

Selecting a Residual Current Device (RCD)

Selecting a Residual Current Device (RCD)
IMPORTANT SAFETY FEATURE
All SolarEdge inverters incorporate a certified internal Residual Current Device (RCD) in order to
protect against possible electrocution and fire hazard in case of a malfunction in the PV array,
cables or inverter. There are 2 trip thresholds for the RCD as required for certification (DIN VDE
0126-1-1). The default value for electrocution protection is 30 mA, and for slow rising current is
300 mA.
If an external RCD is required by local regulations, check which type of RCD is required for the relevant
electric code. Install the residual-current device (RCD) in accordance with the applicable local standards
and directives. SolarEdge recommends using a type-A RCD. The recommended RCD value is 100 mA or 300
mA unless a lower value is required by the specific local electric codes. When required by local regulations,
the use of an RCD type B is permitted.
NOTE
For multiple inverters, an RCD per inverter is required.
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. T he following steps are recommended to
avoid nuisance tripping of the external RCD:
Select the appropriate RCD f or correct operation of the installation: An RCD with a rating of 30 mA
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may actually trip at a leakage as low as 15 mA (according to IEC 61008). High quality RCDs will typically
trip at a value closer to their rating.
Configure the trip voltage of the inverter's internal RCD to a lower value than the trip current of the
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external RCD. The internal RCD will trip if the current is higher than the allowed current, but because
the internal inverter RCD automatically resets when the residual currents are low it saves the manual
reset.
For detailed information, refer to the RCD Selection for SolarEdge Inverters Application
Note, available on the SolarEdge website at
http://www.solaredge.com/sites/default/files/application_note_ground_fault_rcd.pdf.
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Single Phase Inverter with HD-Wave Technology Installation MAN-01-250-1.2