UNIVERSITY MALAYSIA PERLIS EKT 101 ELECTRIC

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EKT 101 Electric Circuit Theory
Module I
UNIVERSITY MALAYSIA PERLIS
EKT 101
ELECTRIC CIRCUIT THEORY
LABORATORY MODULE 1
INTRODUCTION I
SEMESTER I (2016/2017)
SCHOOL OF COMPUTER AND COMMUNICATION ENGINEERING
SEM I 2015/16
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
INTRODUCTION TO LABORATORY I
BASIC COMPONENT
OBJECTIVES
1. To introduce students with the basic component and to acquaint the skill to read its values
based on color code and digital/alphabet code.
2. To familiarize student to handle power supply and in using breadboard.
INTRODUCTION
1.
BASIC COMPNENT
i. RESISTOR
The color code technique is used to show resistance values of carbon resistors without having to
measure it. In this technique color bands are printed on the resistor. The procedure for
determining the resistance of a color-coded resistance is described in Table 1. The first two bands
determine the first two digits of the resistor value, while the third band determines the power of
10-multiplier. For the resistor with value less than 10  the third band is either silver or gold. The
forth band is the percent tolerance for the chosen resistor. If resistors have only three bands, it
means the forth band has no color. Sometimes a fifth band is employed for some high precision
resistor where the first three bands represent the significant digit. The forth band is the multiplier
while the fifth band is the tolerance. In the other case, for some standard 4-band code, a fifth band
may indicate the manufacturer’s special code for some physical characteristic or failure rate of the
component.
In writing the value of resistors: k stands for multiplier “kilo” and M for multiplier “mega”. The
alphabet written after the resistor value shows the tolerance: F = 1%, G = 2%, J = 5%, K= 10%
and M = 20%.
The standard code is adopted by manufacturer through their trade association, the Electronic
Industries Association (EIA).
.
SEM I 2015/16
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Color
Black
Brown
Red
Orange
Yellow
Green
Blue
Violet
Grey
White
Gold
Silver
No Color
Module I
1st Band
(1 Significant
Digit)
0
1
2
3
4
5
6
7
8
9
st
2nd Band
(2 Significant
Digit)
0
1
2
3
4
5
6
7
8
9
nd
3rd Band
(Multiplier)
4th Band
(Tolerance)
1
101
102
1 03
104
105
106
107
108
109
0.1
0.01
-
1%
2%
3%
4%
5%
10%
20%
Table 1: Resistor color coding
Figure 1: Reading resistor color coding
Example 1:
The value of this resistor is 25 x 101±
10% = 250± 10% ohms
Minimum value – 225 
Maximum value – 275 
SEM I 2015/16
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
Example 2:
R33F = 0.33 ±1% 
4k7 = 4.7 x 103 
10R0 = 10 
200R = 200 
6k8J = 6.8 x 103  ±5%
R39 = 0.39 
2k2M = 2.2 x 103 ±20%
1R0 = 1 
ii. CAPACITOR
Same as resistors, most of the capacitors have their nominal value printed directly on them using
digital/alphabet code according to the EIA coding system. This code is generally given in
picofarads (pF), which means that we need to manipulate the value if we want the value in
microfarads (F) or nanofarads (nF). Some capacitors have polarity (positive and negative) which
must be connected according to their polarity in order for the capacitor to operate such as the
electrolytic capacitors. Normally the negative leg of electrolytic capacitor could be recognized by
the white stripes at the body and/or the negative leg is shorter than the positive leg.
Some types of capacitors are shown in Figure 2 below.
Figure 2: Different types of capacitors construction
Example 3:
Capacitor marked 104 has value of 10 with 4 zeroes after it, or 100,000pF (equivalent to 100 nF
or 0.1 F)
Capacitor marked 681 = 68 with single zero or 680 pF
Capacitor marked 472 = 47 with 2 zeroes or 4700 pF (equivalent to 4.7nF)
Example 4:
Capacitor marked 220n has 220nF capacitances (equivalent to 0.22F)
Capacitor marked 3n3 has 3.3nF capacitances (equivalent to 3300pF)
Some of the capacitors have a capital letter to indicate their tolerance rating. Below is capacitor
tolerance marking codes:
F
 1%
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G
 2%
J
 5%
K
 10%
M
 20%
Z
-20%, +80%
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
Example 5:
104K = 0.1F  10%,
4n7J = 4.7nF  5%
iii. INDUCTOR
An inductor is a passive electronic component that stores energy in the form of a
magnetic field. In its simplest form, an inductor consists of a wire loops or coil. The
inductance is directly proportional to the number of turns in the coil. Inductance also
depends on the radius of the coil and on the type of material around which the coil is
wound. The standard unit of inductance is the Henry, abbreviated H.
Figure 3: Different types of Inductor
How to read Inductor Value
Figure 4: Inductors





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Note that the values are in micro Henries (μH)
First two digits are the value
Third digit is the multiplier
If there is an R, its acts as a decimal point, and there is no multiplier
Examples:
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
101 = 10*101μH = 100μH
4R7 = 4.7μH
Suffix
 Sometimes the precision of the inductor will be marked, using a final letter F,
G, J, K, or M
 F = +/-1%
 G = +/-2%
 J = +/-5%
 K = +/-10%
 M = +/-20%
2.
BREAD BOARD
When building a "permanent circuit" the components can be "grown" together (as in an integrated
circuit), soldered together (as on a printed circuit board), or held together by screws and clamps
(as in house wiring). In lab, we want something that is easy to assemble and easy to change. We
also want something that can be used with the same components that "real" circuits use. Most of
these components have pieces of wire or metal tabs sticking out of them to form their terminals.
A breadboard is used to make up temporary circuits for testing or to try out an idea. No soldering
is required so it is easy to change connections and replace components. Parts will not be damaged
so they will be available to re-use afterwards.
Figure 3: Front look of a typical small breadboard used in the laboratory
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Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
The breadboard has many strips of metal (usually copper) which run underneath the board.
Figure 4: The metal strips layout
When wiring, it is important to keep your work neat! This will save time in debugging when your
circuit doesn’t work. Here are some tips: Keep your wires short, do not loop wires over the chip,
use the bus lines for Ground or a DC supply voltage (e.g. VCC) and sometimes to get cleaner
signals, short the metal base of the breadboard to the circuit’s ground.
3. B. POWER SUPPLY
A power supply as depicted in Figure 5 is a device that supplies electric power to an electrical
load. The term is most commonly applied to devices that convert one form of electrical energy to
another, though it may also refer to devices that convert another form of energy (mechanical,
chemical, solar) to electrical energy. A regulated power supply is one that controls the output
voltage or current to a specific value; the controlled value is held nearly constant despite
variations in either load current or the voltage supplied by the power supply's energy source.
SEM I 2015/16
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
Figure 5: Power Supply
Characteristic:
Have 3 channels – Channel 1 & Channel 2 – 0-30 V / 0- 50 V
Channel 3 – Fixed 5 V
SEM I 2015/16
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
UNIVERSITY MALAYSIA PERLIS
EKT 101
ELECTRIC CIRCUIT THEORY
EXERCISE 1
SEMESTER I (2015/2016)
SCHOOL OF COMPUTER AND COMMUNICATION ENGINEERING
SEM I 2015/16
Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
EQUIPMENT/COMPONENT
Resistor
Breadboard
Capacitor
Inductor
Power Supply
EXERCISES
Complete all tables
PART A: READING RESISTOR BY COLOR CODING
Determine the nominal value or color bands of a particular resistor based on color coding
technique for each case given in Table 2 below.
No.
1.
2.
3.
4.
5.
6.
7.
Band 1
brown
blue
yellow
red
COLOR BAND
Band 2
Band 3
black
red
grey
brown
violet
orange
red
orange
Band 4
gold
gold
gold
gold
Nominal Value
3.9k ± 5%
15k ± 5%
27k ± 5%
Table 2: Exercise for determining resistor values by color coding and measurement
PART B: READING RESISTOR AND CAPACITOR BY DIGITAL/ALPHABET
CODING
Determine the nominal value of a particular resistor based on digital/alphabet coding technique
for each case given in Table 3 below.
DIGITAL/ALPHABET CODE
3k9
1R0
8M5
R56
NOMINAL VALUE (in ohm)
Table 3: Exercise for determining resistor values by digital/alphabet coding
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Introduction Laboratory I
EKT 101 Electric Circuit Theory
Module I
DIGITAL/ALPHABET CODE
33J
104
3n3J
103Z
NOMINAL VALUE (in nanofarad)
Table 4: Exercise for determining capacitor values by digital/alphabet coding
PART C: READING BASIC COMPONENT VALUE
Given a set of component, identify all the values. Write the color and values in table below.
No.
Band 1
COLOR BAND
Band 2
Band 3
Band 4
Nominal Value
PART D : CAPACITOR AND INDUCTOR
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Introduction Laboratory I
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