How many wires does a 3Φ, 4-wire service contain?

A 3-phase, 4-wire service contains four conductors, which typically consists of three phase wires and one neutral wire. In a 3-phase system, the three phase wires are responsible for carrying alternating currents that are out of phase with each other, facilitating the efficient transfer of electrical power. The fourth wire, which is the neutral, serves as a return path and balances the load across the three phases.

This configuration is commonly used in various electrical installations because it allows for both three-phase and single-phase loads to be connected to the system. It improves efficiency and can help manage the voltage levels, especially in industrial and commercial settings.