On a three-way, there’s an extra terminal, known as the “common.” Power comes in to your switch on the prevalent, then two “traveler” wires join the very first switch to the next around the brass terminals. If the switch is on, electricity flows with the switch within the inbound wire https://wiring-to-switches43852.yomoblog.com/41456514/the-greatest-guide-to-smart-power-point