In accordance to IEC 62305 and the special requirement of solar system, below points should be considered when categorizing surge protection zones and selecting/ installing the SPD:
1. Lightning protection zone (LPZ 0…3);
2. Relative SPD test waveshapes (8/20 μs or 10/350 μs);
3. Voltage protection level (especially the UP value of SPD AC side);
4. Open circuit voltage at the DC side;
5. Harmonic wave interference
In accordance to:
1. IEC 61643-31: Low-voltage Surge Protective Device for Specific Application including d.c.
2. IEC 62305: Protection against Lightning
3. IEC 61312: Protection against Lightning Electromagnetic Impulse
4. IEC 61643-11: Low-voltage Surge Protective Devices
T2 SPD and PV series are used in DC combiner boxes; T2 PE...30(R) series is used in AC combiner boxes.
T2 SPD and PV series products are used in DC distribution cabinets.
Rail-mounted T1+T2 or T2 SPD, PTV or PV series are used on the DC side of the inverter, and PCB onboard PV...M series products can also be adopted.
T2 PE 385-40M2-32R is used in 230/400 Vac power supply systems; T2 PE 760-25M2-32R is used in TNC power supply systems with higher voltages
PA2 type relays are used in micro-inverter AC systems and string-type insulation detection systems.
Relays of type PB3, PC3 and PC6 are suitable for controlling the AC systems (220~1000 Vac) of 5~300 kW string inverters.