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Industrial Electrical Print Reading Classes for Your Place of Business


Industrial Electrical Print Reading Classes for Your Place of Business

Anyone who works with electricity needs to be able to read industrial electrical prints. No matter what industry you are in, if your workers deal with electricity, they should master the skill of reading and interpreting electrical blueprints, construction blueprints, and architectural electrical drawings.

For instance, an architect who designs a project works with a number of consultants creating a set of blueprints. At least one of these sets will be the electrical blueprints, showing the proposed construction of the electrical system. The drawings will show light switches, receptacles, wires, light fixtures, and anything else that must be powered by electricity.

Signs, Lines, and Symbols

One of the first things a user of electrical plans must learn is how to interpret all those electrical signs, lines, and symbols used in blueprints. They may seem very mysterious at first, but most users become adept at interpreting the markings quickly. Mastering the symbols will help the reader of the plans increase project efficiency by deciphering and comprehending symbols accurately and effortlessly.

Standardized symbols are to be found in all construction plans and specs so that users will maintain consistent interpretation of the plans, which helps them place electrical systems correctly. The National Electrical Contractors’ Association issues a publication, NECA 100, Symbols for Electrical Construction Drawings, as a resource for standardizing the symbols, and assuring consistency of use. NECA 100 is commonly used in apprenticeship programs to train electrical workers in blueprint reading.

Understanding Blueprints

Keys to help interpret plans are always included in architectural, construction, or electrical drawings. Knowing where the keys are will help the user understand the plans. Here are some additional tips on understanding these blueprints.

  • The symbol legend explains which symbol represents which electrical component. Legends are usually found on a title page or the first page of the drawings.
  • Electrical plans help the user understand wiring diagrams. They show the path wires should take from the equipment and back to the panel. The numbers on the wires indicate the breaker from which the wire will be run. The user can see which pieces of equipment will be grouped on a breaker.
  • Electrical blueprints help the user see how lights in a room or equipment in a section of a building may be grouped — a practice known as phasing. The user needs to pay attention to which items are phased together, and determine if they are grouped in the right manner.
  • Electrical blueprints allow the user to view the lighting plan. Often a separate set of plans from the wiring drawings, this plan shows type of light fixtures and layout.

Typical Electrical System Plans

Drawings for most electrical systems in commercial, industrial, and bigger residential projects typically have the following:

  1. Plot plan. To-scale plan shows location of the building on the property, with outside wiring.
  2. Floor plans. These show walls and partitions for each floor, along with wiring and outlets for power, lighting, signal, communication, and related electrical equipment. Building partitions should be drawn to scale, as should panel boards, switchgear, and fluorescent lighting fixtures. Locations of electrical outlets must be readable.
  3. Power-riser diagrams. Show service entrance, panel board components.
  4. Control wiring schematic; single-line diagrams.
  5. Notes, schedules, large-scale details.

Learning to Read Electrical Blueprints

Workers in a diverse range of jobs can profit from the knowledge of reading electrical blueprints. If your operation has employees in these roles, you may want to consider providing the training:

  • Machine operators
  • HVAC technicians
  • Mechanics
  • Alarm technicians
  • Apprentices
  • Electricians
  • Stationary engineers
  • Non-electrical engineers
  • Plant and facility managers
  • Facility managers

You should also consider cross training multi-craft personnel in how to read electrical blueprints.


A typical training teaches students proper interpretation of electrical drawings and construction blueprints. Students also learn how to apply National Electric Code (NEC) compliance rules, and how to look for errors. Trainings generally offer examination and discussion of basic electrical concepts, including voltage drop, short-circuit analysis, conductor fill, kVA ratings, and service calculations.

Typical topics that might be covered are:

  • How to read and interpret prints: drawing layout and reading different electrical prints.
  • Single-line type diagrams: block diagrams; power risers; wiring diagrams; device function numbers; IEEE (Institute for Electrical and Electronics Engineers) and IEC (International Electrical Code) symbols for devices found on schematic diagrams; and electrical schematic diagrams.
  • Architectural electrical drawings and construction blueprints: plan views; floor plans; sections; elevations; pictorial views; schedules; detail drawings; electrical devices; and corresponding ANSI recommended symbols.
  • Basic electrical drawings
  • Common components: applications; operation; NEMA (National Electrical Manufacturer Association) and IEC symbols.
  • Troubleshooting: manual and automatic circuits; typical problems; voltage; resistance; and continuity checks.

If you’re convinced your employees could benefit from learning to read electrical prints properly, why not contact NTT and learn about our Electrical Print Reading seminar? For more information and to set up a training seminar, contact NTT today.


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