interface - FASGREL

wietap DC SolarOvervoltage protection forPhotovoltaic systemsPhotovoltaic systems, abbreviatedas PV systems, are a considerableinvestment that must be protectedfrom failure and damage. As thesesystems are installed outdoors, theyare exposed to the danger of overvoltagefrom lightning strikes.Overvoltage protection in the DCcircuit with central invertersThe generator circuit (the PVmodules) produces a direct current.Connecting the PV modules andarrays in series allows voltagesof 1000 V to be reached. Thiscombination with the fact that thegenerator circuit can continue tosupply energy after overvoltagerequires sophisticated technology forthe overvoltage arrester.DC overvoltage protection:The PV/DC overvoltage arrestersare specially designed for use in PVsystems.Both the housing technology andthe connections are designed forthe requirements of a PV systemshigh voltages and conductor crosssections.With a width of only 36 or48 mm, the units are easily installedinside distribution panels, requiringthe minimum of space.DC■ High discharge capacity due topowerful zinc-oxide varistor■ No fire hazard caused by permanentelectric arc due to combineddisconnect and short-circuit facility.Overload indicated in display window■ Signaling contacts for remotemonitoring in all remote signaling typesAC overvoltage protection:On the AC side of the invertersovervoltage protection must also beinstalled. The arresters listed here arethe most commonly used versions.Suitable units can be found inside thechapters wietap IEC and wietap UL/CSA.33