Appendix C: Safedc - SolarEdge SE8K-N4 Installation Manual

Appendix C: SafeDC™

Appendix C: SafeDC™
When AC supply to the inverter is shut off (by shutting off the AC breaker at the site), or when the
inverter ON/OFF/P switch is turned to OFF, the DC voltage drops to a safe voltage of 1V per optimizer.
The SolarEdge inverters are certified for compliance with the following standards as disconnection
devices for PV generators, meaning that they can replace a DC disconnect:
IEC 60947-3:1999 + Corrigendum: 1999 + A1:2001 + Corrigendum 1:2001 + A2:2005;
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DIN EN 60947-3
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VDE 0660-107:2006-03
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IEC 60364-7-712:2002-05
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DIN VDE 0100-712:2006-06.
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In compliance with these standards, the disconnection mechanism operates as follows:
1. Turn the inverter ON/OFF/P switch, located at the bottom of the inverter, to OFF, or disconnect the
AC by shutting off the AC breaker at the site. The DC voltage displayed on the inverter LCD begins to
decrease.
If the AC breaker was shut off, the LCD does not display. In this case, wait five minutes.
2. When the DC voltage reaches a safe voltage, the PV connectors at the input to the inverter can be
disconnected. A galvanic separation then exists between the PV array and the inverter.
WARNING!
SafeDC complies with IEC60947-3 when installing the system with a worst case SafeDC voltage (under
fault conditions) < 120V.
The worst case voltage is defined as: Voc,max+ (String Length-1)*1V,where:
Voc,max = Maximum Voc (at lowest temperature) of the PV module in the string (for a string with
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multiple module models, use the max value)
String Length = number of power optimizers in the string
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Three Phase Inverter with synergy technology Guide MAN-01-00402-1.1