Engineering H192 - Computer Programming
Product Analysis
Lab 3
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 1
Engineering H192 - Computer Programming
Product Analysis Objectives
• Combine previous lab experiences to better
understand the workings of a completed product.
• Develop an appreciation for horsepower and
wattage considerations in product design.
• Expand the library of electrical schematic
symbols used to designate components.
• Develop reverse engineering skills.
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 2
Engineering H192 - Computer Programming
Product Analysis
Contents:
• Power Conversion and Approximation
• Schematic Components
• Motor Discussion
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 3
Engineering H192 - Computer Programming
Power Conversion
watt [for James Watt], abbr. W, unit of power, or
work done per unit time, equal to 1 joule per
second. It is used as a measure of electrical and
mechanical power. One watt is the amount of
power that is delivered to a component of an
electric circuit when a current of 1 ampere flows
through the component and a voltage of 1 volt
exists across it.
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 4
Engineering H192 - Computer Programming
Power Conversion
horsepower, unit of power in the English system of
units. It is equal to 33,000 foot-pounds per
minute or 550 foot-pounds per second or
approximately 746 watts. The term horsepower
originated with James Watt, who determined by
experiment that a horse could do 33,000 footpounds of work a minute in drawing coal from
a coal pit.
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 5
Engineering H192 - Computer Programming
Schematic Symbols
Commonly Used Symbols:
DC Source
AC Source
Motor
Ground
Resistor
Capacitor
Fuse
SPST Switch
N.C. Push
Button
Switch
N.O. Push
Button
Switch
Winter Quarter
Female
Connector
Gateway Engineering Education Coalition
Male
Connector
Lab 3
P. 6
Engineering H192 - Computer Programming
Breakaway View
Stator
Winding
Rotor
Laminated Core
Poles “Shaded”
with Copper Wire
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 7
Engineering H192 - Computer Programming
Shading Theory
Shading Coils Rotor
Stator Winding
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 8
Engineering H192 - Computer Programming
Shading Theory
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 9
Engineering H192 - Computer Programming
Shading Theory
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 10
Engineering H192 - Computer Programming
Shading Segments
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 11
Engineering H192 - Computer Programming
Flux Wave Rotation
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 12
Engineering H192 - Computer Programming
Motor Speed
• Motor theory tells us that the speed of an ac
motor is directly proportional to the frequency
and inversely proportional to the number of poles
as follows:
120 fs
rpm =
N
p
• Thus, for a 2-pole motor running at 50 hz:
120 x 50
rpm =
= 3000
2
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 13
Engineering H192 - Computer Programming
Motor Slip
• The rotor of an induction motor will not rotate at
the theoretical speed due to slip. The equation
for slip is: rpm
 rpm
theoretical
rpmtheoretical
actual
100  % slip
• Thus, if the anticipated rpm was 3600 and the
actual rpm was 3440:
3600  3440
 100  4.44% slip
3600
Winter Quarter
Gateway Engineering Education Coalition
Lab 3
P. 14