Electrical construction symbols provide a standardized, universal language for representing various electrical components and circuits in a drawing. They enable engineers, electricians, and other construction professionals to communicate clearly and streamline the design process. NECA 100-2024: Symbols for Electrical Construction Drawings provides specifications for symbols used on electrical construction drawings.
Electrical Construction Drawing Symbols
Electrical construction drawing symbols serve as a visual language to represent different electrical components, such as switches, outlets, fixtures, and wiring. Symbols are a shorthand way of showing the locations, types, and sizes or ratings of electrical wiring and equipment as well as the interrelationships between these items. They allow electricians and engineers to easily understand the layout and placement of an electrical system and assure accurate project execution across various locations.
Electrical construction drawings should be supplemented with specifications in order to establish the details (e.g., specific materials, installation methods, and other technical aspects of the electrical system that may not be fully captured by the drawings alone) of electrical systems. NECA 100-2024 functions as the resource for those specifications, assuring a complete understanding of the project requirement.
What Is NECA 100?
NECA 100-2024 describes graphic symbols used to represent electrical wiring and equipment on construction drawings. In this publication, the term “electrical” is used to include electrical, electronic, and communications systems covered by the National Electrical Code (NFPA 70). NECA 100-2024 also summarizes recommended drawing practices for electrical construction drawings. For example, the standard details that different electrical systems, such as power distribution, luminaire, voice/data, fire alarm, and security/access control should be shown on separate plans if combining them on the same drawings would reduce clarity.
This standard is limited to North American symbols for electrical wiring and equipment.
Electrical Circuitry Symbol Design Specifications in NECA 100
The symbols in NECA 100-2024 are widely understood by those in the electrical design and construction field. The standard details that every symbol making up part of an electrical circuit must begin with and end with another symbol. When a circuit continues on a different drawing, the end of the circuitry symbol should be appropriately noted on both drawings. This circuitry continued notice is necessary for both vertical and horizontal circuits.
Furthermore, NECA 100-2024 specifies that the angle at which a circuitry symbol meets another symbol has no particular significance unless otherwise noted. Circuits normally meet one another at a junction box, pull box, or piece of electrical utilization or communications equipment. Future circuits and future equipment should be indicated by dashed lines and clearly marked as future circuits or future equipment on every drawing where applicable.
NECA 100-2024: Symbols for Electrical Construction Drawings is available on the ANSI Webstore.