Wiring Direction: Wiring between the main circuit breaker and each branch circuit breaker in the box generally goes on the left, and the wiring out of the distribution box generally goes on the right. Binding Requirements: The wires should be bound with. The line wire is the conductor that brings power directly from the electrical panel, also known as the source, into the switch box. The. This guide explains how to wire a standard single-pole light switch safely, including common switch wiring configurations, step-by-step instructions, troubleshooting tips, and updated wiring diagrams. Typical 120V branch circuits.