Which color is commonly used to indicate two phases in a two-pole electrical switch?

In electrical installations, the color coding of wires plays a crucial role in ensuring safety and proper functionality. Black is commonly used to signify one of the live phases in a two-pole electrical switch. When dealing with a system involving two phases, it is standard practice to use black for one phase and another color, often red or another distinct shade, to represent the second phase. This method helps in clearly identifying the live connections when installing or maintaining electrical systems.

Understanding this color coding is essential for electricians, as it ensures that they can work safely and effectively, minimizing the risk of short circuits or accidental contact with live wires. The option of black in this context is significant because it aligns with the National Electrical Code (NEC) and other wiring standards that dictate the use of black for hot (live) wires.