CSLB C-10 Electrical ContractorPlanning and EstimatingEasy

An electrical contractor is reviewing blueprints for a new commercial office building. The blueprints indicate a symbol that is a square with a diagonal line from one corner to the opposite, with the letter 'R' inside. What does this symbol typically represent?

  1. ASpecial purpose receptacle
  2. BFloor box receptacle
  3. CRecessed light fixture
  4. DDuplex receptacle, switched
Show answer & explanation

Correct answer: C. Recessed light fixture

A square with a diagonal line and the letter 'R' typically represents a recessed light fixture on electrical blueprints, indicating its mounting type and function.

Why the other options are wrong

  • A. A special purpose receptacle often uses a standard receptacle symbol with a subscript (e.g., 'WP' for weatherproof) or a note.
  • B. A floor box receptacle is usually indicated by a circle with 'F' or 'FB' and sometimes a receptacle symbol inside.
  • D. A duplex receptacle, switched, typically uses a standard receptacle symbol with a line connecting to a switch symbol.

Architectural Electrical Symbols

Standardized graphical representations used on blueprints to depict electrical components, devices, and systems.

  • Symbols provide a universal language for electricians and designers.
  • Understanding symbols is crucial for accurate material takeoffs and installation.
  • Variations exist, but many core symbols are widely recognized, often defined in a legend.

Memory trick: Lighting symbols: 'Shapes' and 'Letters' tell you 'Where' and 'What'.

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