Determines installations and repairs including types, sizes, gauges, lay out of conduit, wiring, couples, fittings, relays, controls, distribution panels, and other electrical devices used in a variety of complete electrical systems including the best methods of installation and repair in compliance with the National Electrical Code. Uses blueprints/schematics of electrical systems to determine the type and extent of repair needed to calculate voltage, current in series or parallel circuits, resistance, inductance, capacitance, current flow, and length of raceways, conduits, and cable trays.