Publisher The Goodheart-Willcox Co., Inc. Tinley Park, Illinois

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PowerPoint Presentation
PublisherThe Goodheart-Willcox Co., Inc.Tinley
Park, Illinois
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Chapter 23

• The Electrical Plan

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Chapter 23 Overview

• Introduction
• Required Information
• Procedure for Drawing an Electrical PlanManual
  Drafting
• Procedure for Drawing an Electrical PlanCADD

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Learning Objectives

• Describe an electrical plan and identify its
  features.
• Identify typical electrical symbols found on a
  residential electrical plan.
• Draw an electrical plan for a residential
  structure using manual drafting techniques.
• Draw an electrical plan for a residential
  structure using CADD.

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Introduction

• The purpose of the electrical plan is to show the
  location and type of electrical equipment to be
  used.
• A plan view in section.
• Usually traced from the floor plan.
• Shows the meter, distribution panel, outlets,
  switches, and special features.
• Identifies number and types of circuits.

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Required Information

• The electrical plans shows
• The service entrance capacity.
• Meter and distribution panel.
• Location, placement, and type of switches.
• Location and type of lighting fixtures.
• Special electrical equipment.
• Number and type of circuits.
• Electrical fixture schedule.

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Required Information

• The electrical plan also includes the symbols, a
  legend (if needed), and notes to describe the
  systems.
• The required amperage rating of the service is
  shown beside the distribution panel.

(continued)
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Common Electrical Symbols
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Service Entrance

• Locate service entrance equipment close to the
  service drop.
• The closer the main breaker is to the meter, the
  better.
• Locate close to largest energy users.
• Larger loads require larger conductors.
• Shorter runs reduce voltage drops.
• Locating the meter outside is desired.

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Switches

• The number and placement of switches is related
  to the number of lighting fixtures, switched
  outlets, equipment.
• Select logical location for each switch.
• Switches may be toggle, quiet switch, silent
  mercury switch, or dimmers.
• Use proper symbols to show the type of switch.

(continued)
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Switches

• Switches are shown on the electrical plan
  connected to the fixtures, appliances, and
  outlets they operate.
• A thin, curved hidden line or centerline is used
  to show the connection.
• These lines do not represent actual wiring, but
  only the elements connected.
• Use SPLINE or POLYLINE in CADD.

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Convenience Outlets

• Place outlets every 6' to 8' along all walls.
• Outlets are usually 120 volt duplex.
• Some duplex outlets may be split-wired to enable
  one outlet to be switched or each outlet on
  separate circuits.
• They are many types of special purpose outlets.

(continued)
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Convenience Outlets

• All convenience outlets should be grounded or
  GFCI to prevent shock.
• Convenience outlets may be switched or always
  hot.
• Consider furniture arrangement when locating
  switches and outlets.
• If a symbol is unique, identify it in a legend.

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Lighting

• The level, or brightness, of lighting is measured
  in foot-candles.
• Sufficient light should be provided for the
  expected activity.
• Two types of lights are generally used
  incandescent light and fluorescent light.
• An incandescent light is the traditional screw-in
  lightbulb.
• A fluorescent light has a tube and is popular in
  kitchens and workshops.

(continued)
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Lighting

• This reading niche requires special lighting.

(continued)
(Georgia-Pacific Corporation)
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Lighting

• Fluorescent lights are also available to replace
  screw-in incandescent bulbs.
• Glare should be minimized except in closets and
  storage areas.
• Lighting fixtures may be permanently attached to
  the ceiling or wall.

(continued)
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Lighting

• The trend is toward more freestanding lamps and
  fewer ceiling-mounted fixtures.
• Consider recessed lighting fixtures for hallways,
  foyers, or special emphasis.
• Track lighting is another option.
• Exterior light fixtures should be rated for
  exterior applications.

(continued)
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Lighting

• Exterior lighting increases safety.
• Plan adequate lighting for walks, drives,
  porches, patios, and other outside areas.
• Use the proper symbol for each lighting fixture
  at the actual location.
• Include a lighting fixture schedule.

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Lighting Fixture Schedule

• A typical lighting fixture schedule that includes
  the necessary information about each fixture.

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Other Devices

• Several other electrical devices should be shown
  on the electrical plan
• Permanent telephone and jacks.
• Intercom system.
• Home security devices.
• TV antenna jack.
• Cable or satellite TV jack.
• Door chimes.
• Audio outlets.

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Branch Circuits

• The number and type of branch circuits should be
  indicated.
• Circuit data is generally shown as a note, chart,
  or diagram on the electrical plan.
• It is not necessary to specify the exact circuit
  for each outlet, but the number of each type
  should be specified.

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Manual Drafting Procedure

• Sequential steps for drawing an electrical plan
• 1. Trace all walls and appliances from the floor
  plan.
• 2. Locate the meter and distribution panel and
  indicate voltage and amperage rating.
• 3. Show all convenience outlets using proper
  symbols.

(continued)
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Manual Drafting Procedure

• This part of a residential electrical plan shows
  the meter, panel box, and other electrical
  features.

(continued)
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Manual Drafting Procedure

• Sequential Steps
• 4. Locate all ceiling and wall lighting outlets
  using proper symbols.
• 5. Show all special outlets and fixtures such as
  telephone, chimes, intercom, security sensors,
  smoke alarms, data jacks, etc.
• 6. Locate the switches and connect them to the
  devices they operate.

(continued)
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Manual Drafting Procedure

• Part of a residential electrical plan showing
  special symbols.

(continued)
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Manual Drafting Procedure

• Sequential Steps
• 7. Add the lighting fixture schedule and symbol
  legend, if necessary.
• 8. List the number and type of circuits required.
• 9. Letter all other notes, title, scale, sheet
  number.
• 10. Check over the drawing.

(continued)
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Manual Drafting Procedure

• Circuit data can be placed in a chart, such as
  this one, and included on the electrical plan.

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CADD Drafting Procedure

• This electrical plan was drawn using CADD.

(continued)
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CADD Drafting Procedure

• Sequential steps for drawing an electrical plan
• 1. Copy all walls and major appliances from the
  floor plan to the electrical plan layer.
• 2. Locate the meter, distribution panel, and
  telephone junction box.
• 3. Insert the proper symbols for all convenience
  outlets.

(continued)
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CADD Drafting Procedure

• Sequential Steps
• 4. Insert the proper symbols for all ceiling and
  wall lighting outlets on the symbols layer.
• 5. Insert symbols for all special outlets and
  fixturestelephone, chimes, security sensors,
  smoke alarms, data jacks, etc.
• 6. Insert the proper symbols for all switches on
  the symbols layer.

(continued)
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CADD Drafting Procedure

• Sequential Steps
• 7. Connect switches to the devices they
  operateuse the POLYLINE command.
• 8. Add the lighting fixture schedule and symbol
  legend, if necessary.
• 9. Add number and type of circuits, notes, title,
  scale, and sheet number.
• 10. Check over the drawing.

(continued)
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CADD Drafting Procedure

• Notice the slight difference in style in this
  CADD-drawn electrical plan. A rendered view of
  the building it represents is also shown.

(ART, Inc.)
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Glossary

• Electrical Plan.
• Shows the location and type of electrical
  equipment to be used in a house.
• Fluorescent Light.
• Has a tube, not a bulb, and is often used in
  schools and businesses.
• Incandescent Light.
• Traditional screw-in lightbulb.
• Lighting Fixture Schedule.
• Identifies the fixtures to be used in a house.