What do ORANGE or YELLOW wires signify?

• A. equipment grounding conductors
• B. AC grounded conductor
• C. wires that remain energized after the machine is disconnected from power. (externally powered)
• D. DC grounded conductors

Answer: (C)

In wiring, color coding helps you spot the function and hazard quickly. Orange or yellow conductors are used to mark circuits that can stay energized even after the machine is disconnected from its main power—these are externally powered. That means they’re supplied by a separate source or feed control or external components, so they may carry voltage even when the machine’s primary disconnect is off. This is why technicians treat them as live and take proper precautions, such as locking out and testing before work. They aren’t equipment grounding conductors (green), nor AC neutral conductors (commonly white/gray), nor DC grounded conductors by standard color practice, so orange or yellow specifically flag external power or externally supplied circuits that remain energized.