Electrical Drawing Symbols and Their Role in Construction

electrical drawing symbolsA successful home build or renovation isn’t complete without the work of a quality electrician. That being said, it’s often a CAD drafter’s job to tell this electrician where to install switches, outlets, and wiring based on electrical drawing symbols within a blueprint.

It’s important to check out these AutoCAD lesson plans because some would argue that the architectural drafter is the key to the quality of the final product. If he or she lays out an efficient wiring strategy the electrician can do their job with ease. On the other hand a cluster of wires and crossovers will have everybody fuming, from the electrician to the homeowner to possibly the house itself if the electrical wiring presents a safety hazard.

True, there is some stress involved in a career as a CAD drafter but perfecting the job can be very rewarding, both professionally and financially. To see more about what’s involved in the creation of these drawings check out this AutoCAD crash course.

The Drafter / Electrician Relationship

The electrical symbols on a blueprint serve as a common language that both drafters and electricians identify with. When a drafter wants to leave no part of the installation to personal judgment, he or she can make the drawing as detailed as possible, from how deep to drill a counterbore to the exact type of lamp to be placed in a corner. An electrician can sometimes use their own discretion when in the field but at the end of the day the blueprint is Gospel.

If problems were to arise in the electrical of the house, the drafter is usually at the top of the hierarchy – which can be good and bad. Many times an electrician who has performed the work for decades will stick with their tried and true ways, even if it’s not to print and they in turn become liable for any damages. On the other hand, if an electrician sees a potential problem but wires to print anyway, the torment falls on the drafter or engineer who released the drawing. It’s best for everybody involved if the drafter and electrician work together as a team, with the laborer seeing how/why drawings are made and the designer getting out in the field and seeing the physical implementation of their prints.

More About Electrical Drawings

If the blueprint is the treasure map of a job site, it’s important to know just what type of information is on display in the drawing. The main schematic on the electrical blueprint is the architectural layout of the home or commercial building. These include a print for each floor of the home with individual rooms clearly labeled. By labeling and identifying the rooms, the designer and electrician can get a better idea of the types of wiring and circuitry that the area needs, for instance a 220v outlet in a utility room or GFCI outlets near water such as a bathroom or kitchen sink.

Electrical Drawing Symbols Legend

What the electrician needs to follow on the blueprint is the symbol legend usually found on the side of the print or the title page of the packet. These symbols give the laborers a reference point so they can complete the job to specs. Sections of the symbol legend include:

  • Wire: Shows the path of the wire throughout the walls of the home. Also includes splicing instructions as to whether wires are connected or not.
  • Switch and Relay: Shows the installers where to place light switches and relays and the specific types of devices to be used. Among the options are the standard toggle switch, multi-switch, push-button switch, and the different relays to be used.
  • Ground: An important aspect of the electrical drawing is identifying ground location and type so that the wires can be connected to the Earth and avoid shock.
  • Resistor: An electrical resistor is placed within the home to limit the amount of electricity that can pass through it. When the electricity passes through the resister, it is transferred into light or heat so the blueprints might show resisters before lightbulbs.
  • Capacitor Inductor: When the electrical system produces too much energy, it is stored in capacitors or inductors throughout the home to regulate the flow. Standard, polarized, and variable capacitor locations are placed on electrical drawings.
  • Lamp/Lightbulb: Electrical drawings are so detailed that they show the exact locations of lightbulbs in every room of the home.

There are dozens if not hundreds of other symbols that might be located on an electrical schematic. Other information that needs to be labeled includes meter, power supply, and diode symbols and miscellaneous features like electric bells, loudspeakers, fuses, busses, antennaes, and much more. It might be beneficial to take this AutoCAD drawing course to get a better idea of how blueprints work, whether the industry becomes a career or just for DIY home use.

Learning the ins and outs of AutoCAD blueprints is very rewarding. A great way to check out if these CAD courses are right for you is through the inexpensive Udemy lessons offered online, like this course: Learning AutoCAD – 3D Modeling and Rendering. With detailed instruction from expert personnel you’ll not only have a better understanding of why electrical components are located in a home, you’ll potentially be the one that puts them there some day.