Tips to protect your equipment from Lightning.
This is my personal opinion getting from basic information to protect equipment from lightning surge.
Protection of PV system using SPD:Surge Protective Device
Home /PV App. /PV spec.SPD Standard for PV system
IEC 61643-31 and IEC 61643-32 are International standard of SPD for PV system. These standards cover test procedure and applications of SPD for PV out-put up to DC 1,500 system. Please check several electric related laws in your country. "Low Voltage line" is up to DC 750V in Japan.
We can see new term "Iscpv(Short-circuit current rating of the SPD)”. This is maximum interrupt current of SPD system.
SPD for PV system ( IEC 61643-31 and 61643-32)
Main test items
Main Test items are the same or similarr those of IEC 61643-11, SPD for low voltage power supply.
Main Test items：
・Operation Duty test for Class1 and 2 SPD： Same as IEC 61643-11 SPD for Low voltage power lines
・Additional Operation Duty Test for Class 1 SPD:Same as IEC 61643-11 SPD for Low voltage power lines
・Thermal Stability Test：Same as IEC 61643-11 SPD for Low voltage power lines
・Failure Test：Declared one of “OCFM: Open-circuit failure mode” or “SCFM: Short-circuit failure mode” before the test.
Disconnector should properly work in both cases. Any damages on circuit do not occure.
Operation Duty Test for Class 1 and 2 SPD
Additional Operation Duty Test for Class 1 SPD
Failure Test：
Use one of simulated PV voltage-current characteristics out-put power supply or Liner voltage-current out-put power supply.
Test should be select OCFM: Open-circuit failure modeor
SCFM: Short-circuit failure mode.
We show Y connection varistor SPD case on this. One of Y branch Module should be replaced with copper bar and the other should be removed before the test.
For OCFM mode case
with PV simulated power supply or Liner out-put power supply:
within 60sec : Iscpv x 2.7
within 20min : 10A (in case of Iscpv is bigger than 10A.)
with Liner out-put power supply(additional test):
with in 5 min with Iscpv
Circuit should be shuted down within specified time without any damage SPD and circuit.
Power supply for the Test
SPD configuration (Y connection SPD）
Again contents in this Web site is my Personal Opnion. I did my best for the contents of this site, but may have some mistakes. We applogize if such things happen. Please remember that we will Not Take Any Resposibilties, even if you take countermeasures for lighting surge following on this contents and have any damage directly on your equipment and/or some other seconday damages.Please do any lightning protection based on your own resposibilty.