Appendix C: Safedc - SolarEdge SE12.5K Installation Manual

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;
DIN EN 60947-3
VDE 0660-107:2006-03
IEC 60364-7-712:2002-05
DIN VDE 0100-712:2006-06.
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 SetApp screen begins to decrease.
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 multiple module models, use the max
value)
String Length = number of power optimizers in the string
Three Phase Inverter with Synergy Technology Installation MAN-01-00402-1.2
Appendix C: SafeDC™ 83