Omron KP100L-OD - 12-2010 User Manual page 39

2 Design
Ground fault breaker / RCD (Residual Current Device)
For KP100L, the use of RCDs type B is not indispensable and RCDs type A can be used.
IEC712.413.1.1.2 describes about Residual Current Devices (RCDs) as follows:
712.413.1.1.1.2
at least simple separation between the AC side and the DC side, an RCD installed to provide
fault protection by automatic disconnection of supply shall be type B according to IEC 60755,
amendment 2.
Where the PV inverter by construction is not able to feed DC fault currents into the electrical
installation, an RCD of type B according to IEC 60755 amendment 2 is not required.
KP100L has built-in fault current protection function required in Germany standard of
VDE V 0126-1-1:2006-02, so DC residual current can be detected and cannot flow to the grid.
Notice of selecting RCD
• The use of RCDs for each unit is recommended.
• In(rated residual operating current of RCD) has to be selected according to the local regulations about the
system configuration, and residual current caused by capacitive characteristic of cable and PV modules.
• In the systems which DC current detection of In<30mA is required, type B has to be used.
• KP100L has built-in fault current protection function but residual current is not zero, so the more KP100L
installed units, the much residual current flows in the grid. When multiple KP100L are installed, downstream
RCD(for KP100L) and upstream RCD has to be determined by consideration of increasing residual current.
• Ultimately, the selection of RCD depends on System Integrators' judgment. OMRON provide this information
for selection of RCDs, but we are not responsible for the selection of RCD.
SPD in Grid side
SPD is used to protect the inverter against lightening surge voltage in AC line.
2 - 6
Where an electrical installation includes a PV power supply system without
Example of SPD
• Class II
• Nominal voltage 230/400 VAC
L1
L2
• Nominal discharge current (8/20us) I
L3
N • Maximum discharge current (8/20us)I
• Protection revel: 1.5 kV
This is just example. Contact company of
protection device for selection.
PE
Grid Connect Photovoltaic Inverte KP100L-OD-USER'S MANUAL
:20 kA
n
:40 kA
max