The 4912F Conductor Fault Locator is a direct reading, semi-automatic calculating bridge operating on the Varley principle. This instrument is designed to locate extremely high resistance shorts, crosses and grounds, such as might occur from minute amounts of moisture in plastic insulated cable (PIC). The 4912F is connected to an access point on the cable and the far end of the cable is strapped to form a bridge configuration. The distance-to-fault result is obtained by a simple sequence of adjustments of the instrument controls. The unit is battery powered, light and compact. It is housed in a rugged fiberglass case and is designed to withstand the demands of field use.