Surge Protection (SPD)

Surge protection defends LED drivers against voltage transients from lightning activity and grid switching, specified in kilovolts per IEC 61000-4-5 test levels. Exposure dictates the rating: indoor fixtures on protected circuits manage with 2–4 kV; street lights, area floods, and anything pole-mounted on exposed feeders should carry 6–10 kV built-in, with 10–20 kV external SPD modules added in lightning-prone regions (a sacrificial, replaceable module protecting the fixture behind it). Surge damage is the leading killer of streetlight drivers in tropical and monsoon climates, and differential (line-to-line) versus common-mode (line-to-earth) ratings both deserve a look in tender specifications.