Parallel Connection

in electrical engineering, the connection of two-terminal networks, which are usually either consumers or sources of electric power, so that the same voltage is at the terminals of the networks. Parallel connections are the principal method of connecting the consumers of electric power; when the source has sufficient power, the connection or disconnection of individual consumers has practically no effect on the operation of the others. In parallel-connected loads that do not contain sources of electromotive force, the currents are inversely proportional to the resistances (direct current) or impedances (alternating current); the total current of a parallel connection is equal to the sum of the currents in all the branches—the algebraic sum for direct current or the vector sum for alternating current. Sources of electric power such as the generators in power plants are connected in parallel when the power of one source is insufficient to supply all the consumers.