Auto Cad for Electrical Eng Student

Module Title

Introduction to AutoCAD

For Electrical Engineering Students

4/29/2010 FKE UTeM sulaimansabikan

Contents

CHAPTER 1. Introduction 6

CHAPTER 2. Exploring the AutoCAD Interface 7

CHAPTER 3. Drawing Setup in AutoCAD 11

CHAPTER 4. Starting A New Drawing 15

CHAPTER 5. Basic Drawing 18

CHAPTER 6. Organizing A Drawing Through Layers 22

CHAPTER 7. Modifying AutoCAD Drawing 23

CHAPTER 8. Text 28

CHAPTER 9. Dimensioning 30

CHAPTER 10. Block Creation in AutoCAD 32

CHAPTER 11. Plotting Your Drawing 35

CHAPTER 12. Template Drawing Creation 37

CHAPTER 13. Isometric Drawing 38

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Module Planning: Introduction to AutoCAD for Electrical Engineering Students

DAY 1

 CHAPTER 1 – CHAPTER 9

DAY 2

 Exercise 1 : Setup Drawing, Geometric Drawing, Basic Drawing, Basic Editing  Exercise 2 : Basic Drawing, Editing, Layer, Text, Dimension

 Chapter 10 – CHAPTER 12

 Exercise 3 : Basic Drawing, Editing, Layer, Text, Dimension, Block

 Exercise 4 : Drawing Setup, 2D Drawing, Editing, Layer, Text, Dimension, Block

DAY 3

 Exercise 5 : Setup Drawing, Geometric Drawing, Basic Drawing, Basic Editing  Exercise 6 : Basic Drawing, Editing, Layer, Text

 CHAPTER 13

 Exercise 7 : Simple Isometric Drawing

 Exercise 8 : Using Template, Title Block, Basic Drawing, Editing, Layer, Text, Dimension

DAY 4

 CHAPTER 14

 Assignment 1 : Electrical Engineering Drawing I using AutoCAD (Assessment 1)  Assignment 2 : Electrical Engineering Drawing II using AutoCAD (Assessment 2)

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Learning Outcomes

After completing this course, students (or participants) will be able to:

1. Navigate

and

configure

the

AutoCAD Interface.

2. Use

the

drawing

commands,

editing commands and dimensions

command in the development of an

engineering drawing.

3. Use the precision drafting tools,

layer functions, text functions,

block functions, plot functions, title

block,

template,

isometric

functions and layout views in the

development of an engineering

drawing.

4. Develop an electrical schematics

drawing, electrical layout drawing,

instrumentation/electrical

circuits

CHAPTER 1. Introduction

1.1

What is AutoCAD?

AutoCAD is a CAD (Computer Aided Design or Computer Aided Drafting) software application for 2D and 3D design and drafting.

1.2 Developer?

Autodesk (http://www.autodesk.com/autocad)

1.3 Sold by?

Autodesk.

1.4 Version?

1982 (AutoCAD Version 1.0) 1997 (AutoCAD Release 14) 2010 (AutoCAD 2011)

1.5 Application Areas

# Architecture, Engineering & Construction

# Automotive & Transportation # Education

# Government

# Manufacturing

# Media & Entertainment # Utilities & Telecommunications

1.6 The AutoCAD Family

 AutoCAD®—General, all-purpose design

 AutoCAD LT®—Professional 2D drafting and detailing  AutoCAD® Architecture—Architectural design  AutoCAD® MEP—Mechanical, electrical, and plumbing

design

 AutoCAD® Mechanical—Manufacturing design  AutoCAD® Electrical—Electrical controls design

 AutoCAD® Map 3D—Spacial data creation and management

 AutoCAD® Civil 3D®—Civil engineering and BIM  AutoCAD® P&ID—Process plant design  AutoCAD® Plant 3D—Plant design

1.7 Website?

www.autodesk.com.my

1.8 File format?

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CHAPTER 2. Exploring the AutoCAD Interface

2.1 Starting AutoCAD

Just double-click on the AutoCAD short cut in the Windows desktop.

2.2 AutoCAD graphics screen

2.2.1 AutoCAD Classic

2.2.2 3D Modeling

2.3 AutoCAD Program Window

The AutoCAD program window is divided into six parts: Menu bar Toolbars Drawing area Command window Status bar Dashboard 2.3.1 Menu bar

Cascade menu Dialogue boxes Fly-out menu

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2.3.3 Drawing area

2.3.4 Command window and Status bar

2.3.5 Dashboard

2.4 Opening an Existing Drawing

Open a drawing Select objects Delete objects

Use dynamic input to enter commands Zoom and pan

Find more information on using AutoCAD (F1)

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CHAPTER 3. Drawing Setup in AutoCAD

3.1 Use a drawing template to start a drawing

When you use a template file, new drawings created from the template automatically use the settings defined in the template. This saves you setup time and helps to make sure each drawing you create follows your company’s CAD standards.

Drawing template files have a

.dwt

file extension.

Some of the settings stored in drawing template files include; Unit type and scale (precision)

Title blocks/borders, blocks, and logos Layer names

Snap, grid, and ortho settings

Grid limits Annotation styles Linetypes

3.2 Set the drawing units

Before you start a drawing, you must first decide what drawing units to use. In AutoCAD, distances are measured in drawing units. In a drawing, one drawing unit may equal one inch, one millimeter, one meter, or one mile.

Before you begin drawing, you decide what one drawing unit will represent. AutoCAD does not include a setting that determines the length of a drawing unit.

After you decide what drawing units to use, you can set the format of the drawing units. The format settings available for linear units include

■ Architectural. A length of 15.5 units displays as 1’-3 1/2” ■ Decimal. A length of 15.5 units displays as 15.5000 ■ Engineering. A length of 15.5 units displays as 1’-3.5” ■ Fractional. A length of 15.5 units displays as 15 1/2 ■ Scientific. A length of 15.5 units displays as 1.5500E+01

For example, a mechanical engineer who works in millimeters would set the format for linear units to decimal. An architect who works in feet and inches, would set the format to architectural. The drawing unit format controls only the display style of the drawing units on-screen, such as in the display of coordinates and values in the dialog boxes and prompts.

To set the format of the drawing units

3.3 Drawing Limits

A0 : 841 mm x 1189 mm A1 : 594 mm x 841 mm A2 : 420 mm x 594 mm A3 : 297 mm x 420 mm A4 : 210 mm x 297 mm

3.4 Set the plot scale

When you plot a drawing, you either

specify a precise scale

or

fit the image

design to the current paper size

.

For example, a distance of one drawing unit typically represents one millimeter or one meter in a metric drawing, while one inch or one foot in real-world units are common in an imperial drawing.

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To plot using a scale.

3.5 Understanding the Model Space and Paper Space

There are two distinct working environments or “spaces,” in which you can create objects in a drawing, model space and paper space.

Use the tabs at the bottom of the drawing area to access model space and paper space. Use the Model tab for model space, and use one or more of the Layout tabs for paper space.

Model Space

Paper Space

In model space, you draw a model of your subject at 1:1 scale. In paper space, you can create one or more layout viewports, dimensions, notes, and a title block to represent a drawing sheet. You can switch between model space and paper space.

You can use layout viewports to access model space from within paper space. A layout viewport is like a picture frame containing a “photograph” of the model in model space.

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CHAPTER 4. Starting A New Drawing

4.1 To start a drawing from scratch with the Create Drawing dialog box

The Create New Drawing dialog box is displayed under the following conditions:  You set the STARTUP system variable to 1 (on).

 You set the FILEDIA system variable to 1 (on).

 You click New on the File menu or Qnew on the Standard toolbar when no drawing template file is specified in the Options dialog box.

Start from Scratch

Use a Template

Use a wizard

4.2 Specify Drafting Setting

Snap Grid Polar Tracking Object Snap Dynamic Input

CHAPTER 5. Basic Drawing

5.1 Command

A commad is an AutoCAD function used to perform some task. Command can be activated by;  Menu

 Toolbar button

 Keyboard Command line

 Command abbreviation  Alt key

5.2 Line

With LINE, you can create a series of contiguous line segments. Coordinate System point.

Absolute Coordinate

x,y

Polar Coordinate

@distance,direction

Relative Coordinate

@x,y

Direct distance Entry

5.3 Circle

You can create circles in several ways. The default method is to specify the center and the radius

5.4 Polygon

You can create rectangles and regular polygons quickly. Creating polygons is a simple way to draw equilateral triangles, squares, pentagons, hexagons, and so on.

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5.5 Hatch Pattern

You can hatch an area using a predefined hatch pattern, define a simple line pattern using the current linetype, or create more complex hatch patterns. One type of pattern is called solid, which fills an area with a solid color.

5.6 Arc

You can create arcs in several ways. With the exception of the first method, arcs are drawn counterclockwise from the start point to the endpoint.

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5.7 Ellipse

The shape of an ellipse is determined by two axes that define its length and width. The longer axis is called the

major axis

, and the shorter one is the

minor axis

.

5.8 Rectangle

Use RECTANG to create closed polylines in a rectangular shape. You can specify the length, width, area, and rotation parameters. You can also control the type of corners on the rectangle—fillet, chamfer, or square.

5.9 Polyline

A polyline is a connected sequence of line segments created as a single object. You can create straight line segments, arc segments, or a combination of the two.

Multisegmented lines provide editing capabilities unavailable for single lines. For example, you can adjust their width and curvature. After you've created a polyline, you can edit it with PEDIT or use EXPLODE to convert it to individual line and arc segments.

CHAPTER 6. Organizing A Drawing Through Layers

Layers are like transparent overlays on which you organize and group different kinds of drawing objects. The objects you create have common properties which include colors, linetypes, and lineweights. An object can inherit these properties from the layer it is drawn or placed on, or properties can be specifically assigned to individual objects.

You can group objects with similar properties together on to a layer. This allows you to modify and manage multiple objects in your drawing from one central point. Changing the property for a layer, will update the property for all objects on the layer.

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CHAPTER 7. Modifying AutoCAD Drawing

7.1 Erase

You can erase objects from your drawing using several methods. Erase them with ERASE.

Select them and then cut them to the Clipboard with CTRL+X. Select them and press DELETE.

7.2 Copy

You can create duplicates of objects at a specified distance and direction from the originals. Use coordinates, grid snap, object snaps, and other tools to copy objects with precision.

7.3 Mirror

You can flip objects about a specified axis to create a symmetrical mirror image.

Mirroring is useful for creating symmetrical objects because you can quickly draw half the object and then mirror it instead of drawing the entire object.

You flip objects about an axis called a mirror line to create a mirror image. To specify this temporary mirror line, you enter two points. You can choose whether to erase or retain the original objects.

7.4 Offset

OFFSET creates a new object whose shape parallels the shape of a selected object. Offsetting a circle or an arc creates a larger or smaller circle or arc, depending on which side you specify for the offset.

You can offset  Lines  Arcs  Circles

 Ellipses and elliptical arcs (resulting in an oval-shaped spline)

 2D polylines

 Construction lines (xlines) and rays  Splines

7.5 Array

You can create copies of objects in a rectangular or polar (circular) pattern called an array. For rectangular arrays, you control the number of rows and columns and the distance between each. For polar arrays, you control the number of copies of the object and whether the copies are rotated. To create many regularly spaced objects, arraying is faster than copying.

7.5.1 Rectangular Arrays

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7.6 Move

You can move objects at a specified distance and direction from the originals.

Use coordinates, grid snap, object snaps, and other tools to move objects with precision.

7.7 Rotate

You can rotate objects in your drawing around a specified base point.

To determine the angle of rotation, you can enter an angle value, drag using the cursor, or specify a reference angle to align to an absolute angle.

To rotate an object

1. Click Modify menu » Rotate. 2. Select the object to rotate.

3. Specify the base point for the rotation. 4. Do one of the following:

 Enter the angle of rotation.

 Drag the object around its base point and specify a point location to which you want to rotate the object.

 Enter c to create a copy of the selected objects.

 Enter r to rotate the selected objects from a specified reference angle to an absolute angle.

7.8 Scale and Stretch

You can resize objects to make them longer or shorter in only one direction or to make them proportionally larger or smaller.

You can also stretch certain objects by moving an endpoint, vertex, or control point.

7.8.1 Scale with Reference

To scale an object by reference 1. Click Modify menu » Scale.

2. Select the object to scale. 3. Select the base point. 4. Enter r (Reference).

5. Select the first and second reference points, or enter a value for the reference length.

7.9 Trim and Extend

You can shorten or lengthen objects to meet the edges of other objects.

This means you can first create an object such as a line and then later adjust it to fit exactly between other objects.

Objects you select as cutting edges or boundary edges are not required to intersect the object being trimmed. You can trim or extend an object to a projected edge or to an extrapolated intersection; that is, where the objects would intersect if they were extended.

If you do not specify a boundary and press ENTER at the Select Objects prompt, all displayed objects become potential boundaries.

7.10 Break to Point and Break

You can break an object into two objects with or without a gap between them. You can also join objects to make a single object.

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7.11 Chamfer and Fillet

A chamfer connects two objects with an angled line. It is usually used to represent a beveled edge on a corner.

CHAPTER 8. Text

8.1.1 Single-Line Text

Command :

TEXT

For short entries that do not require multiple fonts or lines, create single-line text. Single-line

text is most convenient for labels.

%%d : simbol darjah () %%p : simbol campur/tolak () %%c : simbol diameter () %%% : simbol peratus (%) %%o : buat garisan atas teks %%u : Buat garisan bawah teks

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8.1.2 Multiline Text

For long, complex entries, create multiline, or paragraph text. Multiline text consists of any

number of text lines or paragraphs that fit within a width you specify; it can extend vertically to an indefinite length.

Regardless of the number of lines, each set of paragraphs created in a single editing session forms a single object, which you can move, rotate, erase, copy, mirror, or scale.

There are more editing options for multiline text than there are for single-line text. For example, you can apply underlining, fonts, color, and text height changes to individual characters, words, or phrases within a paragraph.

CHAPTER 9. Dimensioning

Dimension styles are the main method used to control the way dimensions look. Using styles you can change the text font, the arrow head style, the relative position of the text, the scale of dimensions and many other parameters. Styles are created using the DIMSTYLE command.

9.1 Dimension Styles

Here is a list of the parts of a dimension along with their descriptions.

Dimensions have several distinct elements: dimension text, dimension lines, arrowheads, and extension lines.

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9.2 The Dimension Style Manager

Creates new styles, sets the current style, modifies styles, sets overrides on the current style, and compares styles.

Lines

Symbols and Arrows Text

Fit

Primary Units

Alternate Units Tolerances

CHAPTER 10.

Block Creation in AutoCAD

10.1 Creating and Inserting a Symbol

To save a drawing as a symbol, you use the Block tool, that can be saved and recalled at any time. You can also use entire existing files as blocks. Block usually consists of smaller components of a larger drawing. Typical examples include doors and windows for floor plants, nuts and bolts for mechanical assemblies and resistor and transistor for electrical schematics.

BLOCK

- Creates a block definition from objects you select.

WBLOCK

- Writes objects or a block to a new drawing file.

Write Block command creates a block similar to to the process used in the BLOCK command. However, this will write the objects directly to a location on the hard disk, which allows the block to be inserted in any type of drawing file.

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Ps:

EXPLODE

- Breaks a compound object into its component objects.

GRIP

You can specify whether a block displays a single grip or multiple grips.

You can specify whether a selected block reference displays a single grip at its insertion point or displays multiple grips associated with the objects grouped within the block.

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CHAPTER 11.

Plotting Your Drawing

11.1 Configuring a Plotter

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CHAPTER 12.

Template Drawing Creation

A template is a drawing file that includes some of the following settings: Unit type and precision

Drawing limits

Snap, Grid, and Ortho settings Layer organization

Title blocks

Dimension and text styles Linetypes

Common blocks Plotter setting

Template files have the extention

.dwt

.

AutoCAD has template which conform to several drawing conventions, including; a. ANSI

b. DIN c. Gb d. ISO e. JIS

CHAPTER 13.

Isometric Drawing

Isometric drawings simulate a 3D object from a particular viewpoint by aligning along three

major axes.

By setting the Isometric Snap/Grid, you can easily align objects along one of three isometric planes; however, although the isometric drawing appears to be 3D, it is actually a 2D

representation. Therefore, you cannot expect to extract 3D distances and areas, display objects from different viewpoints, or remove hidden lines automatically.

If the snap angle is 0, the axes of the isometric planes are 30 degrees, 90 degrees, and 150 degrees. Once you set the snap style to Isometric, you can work on any of three planes, each with an associated pair of axes:

Left. Aligns snap and grid along 90- and 150-degree axes. Top. Aligns snap and grid along 30- and 150-degree axes. Right. Aligns snap and grid along 30- and 90-degree axes.

To turn on an isometric plane

 Click Tools menu » Drafting Settings.

 In the Drafting Settings dialog box, Snap and Grid tab, under Snap Type, select Isometric Snap.

 Click OK.

You can cycle through the three isometric planes by pressing

F5

.

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CHAPTER 14.

Engineering Drawing

An engineering drawing, a type of technical drawing, is created within the technical drawing discipline, and used to fully and clearly define requirements for engineered items.

Technical Drawing disciplines,

 Lines style and Types

 Dimension Techniques and tolerance

 Scales

 Multiple views and projections

 Sectional View Isometric Projection

 Orthographic projection

 Isometric projection

 Auxiliary projection

 Symbols and Conventions

 Computer-Aided Drafting

ISO 128 is an international standard (ISO), about the general principles of presentation in technical drawings.

Engineering drawings created by computer-aided design (CAD).

Electrical Engineering Drawing

1. Wiring schematic drawing

2. Electrical floor plants and panel layouts 3. Motor electrical schematics

4. Interconnection drawings 5. Cable/conduit plans

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                   



                   

47

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Exercise 1

BASIC GEOMETRICAL OBJECT AND ELECTRICAL SYMBOLS

LAYER :

Layer Color Linetype

0 White Continuous

Objek White Continuous

Cline Red Center

Dimension Cyan Continuous

Hline Yellow Hidden

Text White Continuous

Exercise 2-A

51

Exercise 2-B

Exercise 03

53

Exercise 04

Exercise 5

Drawing Legend

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Exercise 6

CADANGAN MEMBINA DAN MENYIAPKAN 4 UNIT BENGKEL BERKEMBAR 1 TINGKAT DAN 12 UNIT BENGKEL TERES 1 TINGKAT, DIKAWASAN IKS PULAU SEBANG LOT PT 1611 DAN 1612 MUKIM PULAU SEBANG DAERAH ALOR GAJAH MELAKA.

SCHEMATIC DIAGRAM

Exercise 7

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Exercise 8

CADANGAN MEREKABENTUK, MEMBINA DAN MENYIAPKAN JETI NELAYAN,

BALAI NELAYAN, GERAI IKAN BAKAR DAN LAIN-LAIN YANG BERKAITAN SECARAREKA DAN BINA (DESIGN AND BUILD) DI MUKIM SERKAM, DEARAH JASIN MELAKA UNTUK TETUAN PERBADANAN KEMAJUAN NEGERI MELAKA.