Newmar GI-30-FS Galvanic Isolator 30A Fail Safe [GI-30-FS]GI 30 FS Galvanic Isolator 30A Fail Safe Installing the Galvanic Isolator between the AC safety ground and DC bonding system blocks most of the low voltage currents and corrosive action seen on the vital metallic components in the saltwater. With the low voltage current blocked, the galvanic corrosion effect on the sacrificial anodes is significantly reduced, while the integrity of the critical safety ground path is maintained. This means a