Solar systems’ exposure to lightning-induced surges increases the potential for damage to your system and/or home. For this reason, SECO Energy recommends that members who own, or are contemplating the installation of a solar system, incorporate quality surge protection devices (SPDs) into the design. The number of SPDs required will depend upon the size, complexity, and specific technology of the solar system. Those with battery storage and/or backup generators require SPDs for each installed interface.
Key considerations when applying SPDs should include the protection of the software to the residence and the inverter from both the solar direct current (DC) input and the alternating current (AC) transfer switch plus all references/connections to the site’s ground should also be protected. The easiest, safest and most cost-effective way of doing this is to employ SPDs on the mounting back panel/plane used to hold the inverter/charger system. For installations utilizing micro-inverter technology, protect the AC connections to the electric distribution system. Note National Electric Code(s) requires all SPDs are ANSI/UL 1449 rated. Direct current (DC) SPDs for inverters, must be specifically labeled for that application. If you cannot confirm the SPDs meet these specifications, do not use the product.
Surge protection for solar systems will vary widely between designs and product types. Thus, you should consult your contractor when developing a surge protection plan.