The connecting cable of electrical appliances like electric iron, wate

The connecting cable of electrical appliances like electric iron, water heater or room heater contains three insulated copper wires of three different colours-red, green and black. Which one of the following is the correct colour code?

Red-live wire, Green-neutral wire, Black-ground wire

Red-live wire, Green-ground wire, Black-neutral wire

Red-live wire, Green-neutral wire, Black-live wire

Red-ground wire, Green-live wire, Black-neutral wire

Answer is Right!

Answer is Wrong!

This question was previously asked in

UPSC NDA-2 – 2018

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The correct colour code among the given options is Red-live wire, Green-ground wire, Black-neutral wire.

Standard colour codes for electrical wiring are used for safety and proper connection. While modern standards in many places use Brown for live, Blue for neutral, and Green/Yellow for earth/ground, older or alternative standards often used Red for live, Black for neutral, and Green for earth/ground. The question uses Red, Green, and Black, indicating reference to such a standard.

In older wiring standards (and sometimes still used in specific applications or regions), the colour coding is typically:
– Live wire: Red (transmits voltage)
– Neutral wire: Black (completes the circuit)
– Earth/Ground wire: Green or Green and Yellow (safety connection to ground)
Based on this established convention using the colours provided, the live wire is Red, the neutral wire is Black, and the ground wire is Green. Option B correctly matches these.

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