Building Electrical works

Electrical Power Systems in Buildings

Electric utilities transmit power from the power plant most efficiently at very high voltages. In the United States, power companies provide electricity to medium or large buildings at 13,800 volts (13.8kV). For small commercial buildings or residential customers, power companies lower the voltage with a transformer on a power pole or mounted on the ground. From there, the electricity is fed through a meter and into the building.

Power Distribution in Small Buildings

Small commercial or residential buildings have a very simple power distribution system. The utility will own the transformer, which will sit on a pad outside the building or will be attached to a utility pole. The transformer reduces the voltage from 13.8kV down to 120/240 or 120/208 volts and then passes the electricity to a meter, which is owned by the utility and keeps a record of power consumption.