Journeyman Electrician Exam (NEC)General Electrical Knowledge and Plan ReadingMedium

A client's existing electrical service blueprint shows a symbol consisting of a circle with a diagonal line through it, crossed by another diagonal line. What does this symbol typically represent?

  1. AWeatherproof Receptacle
  2. BFloor Outlet
  3. CSpecial Purpose Outlet
  4. DDuplex Receptacle
Show answer & explanation

Correct answer: C. Special Purpose Outlet

In electrical blueprints, a circle with a single diagonal line typically denotes a duplex receptacle. Adding another diagonal line, making an 'X' inside the circle, generally signifies a special purpose outlet, indicating it's for a specific appliance or voltage.

Why the other options are wrong

  • A. A weatherproof receptacle is usually a circle with 'WP' or 'GFI' (for GFCI) inside or adjacent.
  • B. A floor outlet is typically a circle with a 'F' or 'FO' inside, or sometimes just a circle with a square around it.
  • D. A single diagonal line through a circle usually represents a duplex receptacle.

Special Purpose Outlet Symbol

The electrical blueprint symbol for a special purpose outlet is a circle with two diagonal lines forming an 'X' inside it, often accompanied by text indicating its specific use or voltage.

  • Used for dedicated equipment or specific voltage/current requirements.
  • Distinguished from general-purpose receptacles.
  • Standardized by ANSI/IEEE for clarity in drawings.
  • Variations exist, but the 'X' within a circle is common.

Memory trick: X marks the 'Special' spot for outlets.

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