In Household wiring, what is the colour of "Earth wire"?
20172021
In Household wiring, what is the colour of "Earth wire"?
- A.
Black
- B.
Green
- C.
White
- D.
Red
Attempted by 22 students.
Show answer & explanation
Correct answer: B
Concept
Household wiring uses three separate conductors, each identified by a standard colour so electricians can wire appliances safely: the Line (Live) wire carries current from the supply, the Neutral wire completes the return path, and the Earth (Ground) wire is a protective conductor that connects an appliance's exposed metal body to the ground so any fault current is safely diverted instead of passing through a person who touches it. In Indian household wiring practice (IS / Indian Electricity Rules), Live is Red and Neutral is Black, while the Earth conductor is Green — the Bureau of Indian Standards also permits marking it green with a yellow line, matching the internationally harmonised IEC 60446 bi-colour code used for protective conductors.
Conductor | Standard colour |
|---|---|
Line / Live | Red |
Neutral | Black |
Earth / Ground | Green |
Application
Matching the offered single-colour options (Black, Green, White, Red) against this convention: Red = Live, Black = Neutral, and Green = Earth (the colour used for protective earthing in Indian household wiring). White does not appear in the standard Indian three-wire colour code at all.
Cross-check
A quick safety cross-check confirms the assignment: if an appliance's metal casing develops a fault (e.g., a live wire touches the casing), the Earth wire must carry that fault current safely to the ground and trip the circuit breaker/fuse, protecting the user from shock. This safety role is why the Earth conductor is given its own distinct, unmistakable colour rather than sharing a colour with Live or Neutral — confirming Green as the correct identification, distinct from Red (Live) and Black (Neutral).