Pad-mounted transformers, also known as ground transformers, function as transformers for underground power lines. Just like their overhead counterparts, they lower the voltage of electricity to appropriate levels for use in structures. These transformers carry large amounts of electric current and contain oil used for internal cooling, so exercise caution around them.
An underground service wire runs from a buried distribution line or pad-mounted transformer to a customer’s meter. Like underground power lines, these wires may either be direct-buried or run through a metal or plastic conduit.