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% SEM I 2015/16 G 2% J 5% K 10% M 20% Z -20%, +80% Introduction Laboratory I EKT 101 Electric Circuit Theory Module I Example 5: 104K = 0.1F 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 SEM I 2015/16 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 SEM I 2015/16 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 SEM I 2015/16 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 SEM I 2015/16 Introduction Laboratory I