The Protection Devices Every Solar System Must Have

Lightning does not need a direct hit to destroy an inverter. A strike hundreds of meters away induces voltage spikes on DC cables that exceed component ratings thousands of times per microsecond. A Type 2 surge protection device clamps those spikes to survivable levels — for roughly 2% of the inverter's price.

DC electricity does not cross zero volts the way AC does, so a DC arc, once started, sustains itself. This is why strings must be protected by gPV-rated fuses and switched by genuine DC isolators — AC-rated components will weld or burn.

A pre-wired combiner box is the clean way to deploy all of it: string fuses, surge protection and an isolator in one IP65 enclosure, labelled and tested, instead of a hand-wired collection of parts.

None of it works without earthing. Panel frames, mounting rails and the SPD all need a low-resistance path to ground. A complete earthing kit with a certified earth rod is the first protection purchase, not the last.