SolarEdge

Selecting a Residual Current Device (RCD)
Connect the DC connectors of each string to the DC+ and DC- connectors according to the
labels on the inverter.
Figure 15: Inverter DC Connections
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. SolarEdge recommends using a type-A RCD. The recommended RCD
value is 100mA or 300mA 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.
In installations where the local electric code requires the use of a lower leakage RCD, the
discharge current of capacitive parasitic leakage may trip the RCD. Use the following
procedure to avoid this problem:
• Select an appropriate RCD to ensure proper operation of the installation. A 30mA RCD
may still trip at 15mA (according to IEC 61008). Good quality RCDs will trip at a higher
value.
• PV modules with low capacitance leakage to the frame are preferable.
For detailed information, refer to the RCD Selection for SolarEdge Inverters Application Note,
available on the SolarEdge website at http://www.solaredge.com/files/pdfs/se-applicationrcd-selection.pdf.
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SolarEdge-Installation Guide MAN-01-00057-3.1