Use the chart in this calculation guide to find the formula you need according to the measure you will calculate. Finding motor hp horse power, kva kilovolt ampere kw input, when motor hp is known kw kilowatts amperes, when kva is. The theory of classical electromagnetism is based on maxwells equations, which provide a unified description of the behavior of electric and magnetic fields as well as their interactions with matter in practice however, circuit designers normally use simplified equations of electricity and magnetism and. In the above formulas 1 is the angle of lead or lag between current and voltage and cos 1 pei power factor or pf. So current amp of motor kw voltage 1 ph or kw sqrt3voltage pf 3 ph. All this formulas are useful for basic calculation in electrical engineering including voltage,ampere,power, efficiency,power factor and many more. Finding motor hp horse power, kva kilovolt ampere kw input, when motor hp is known kw kilowatts amperes, when kva is known. The treatment throughout the handbook is practical with very little emphasis on theory. Course syllabus elpt 11 basic electrical theory c a ta l o g d e s c r i p ti o n. Example 1 determine the current flowing through the electric heater have p. Ohms law formula and how it is used for determining electrical loads as it pertains to watts, volts and amps. This portable document format pdf file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. When ac theory is introduced, and especially when there is a bias towards radio frequencies, the very first new idea required by many people at least is a correct understanding of the word electricity.
A basic understanding of electrical theory is important in order to understand your job as a construction electrician. Sep 14, 2016 dear viewer, especially for you, here is the free download of electrical formulas, theorems, definitions, laws, connections, symbols, circuits, units, equations pdf special reference copy. Three phase formulas do not use 2 for threewire, two phase circuits, the current in the common conductor is 1. In series combination, the current remains the same through the resistance network. Electrical charts, tables and formulas musco engineering. Journeyman electrician theory quiz 10 electrician exams. If we know the power in watts of an appliance and how many seconds it is used we can calculate the number of joules of electrical energy which have been converted to sortie other. The most fundamental law in electricity is ohms law or vir. Engineers mininotebook formulas, tables and basic circuits. The unit of energy is the joule, the unit of power is the watt, and the unit of time is the second. Understand the electrical principles of alternating current ac.
Scientists, such as faraday, ohm, lenz, and kirchoff have found that electricity seems to behave in a constant and predictable manner in a given condition. Electrical theory alternating current direct current. The v is for voltage, which means the potential difference between two charges. Electrical circuit calculations series circuits many circuits have more than one conversion device in them i. These formulas are carefully explained and demonstrated throughout the book. For every 20 rotations in the secondary, there is one rotation in the primary. Basic electrical theory assessment exam proprofs quiz. Electrical charts, tables and formulas minimum size grounding conductors for grounding raceways and equipment from nec table 250122 rating or setting of automatic overcurrent device in circuit ahead of equipment, conduit, etc. Click on the doe seal below to move to the overview. Electrical formulas, theorems, definitions, laws, connections. Understand the requirements and configurations of electrical circuits.
Chapter 1 advanced electrical theory seabee magazine. The symbol font is used for some notation and formulae. Electronic formulas ohms law formulas for dc circuits. An electrical distributor supplying everything from light bulbs and dimmers to plcs and industrial automation equipment. Common electrical units used in formulas and equations are. The letter k is used in the electrical trade to abbreviate the metric prefix kilo, which represents a value of 1,000. However, the author of this site shall not be held liable for the use of the information or of its consequences. Electrical theory, alternating current, direct current, basic electrical theory, mike holt electrical theory books, videos and libraries. I hope it can make your basic understanding about electrical calculation is clear. Familiarity with trigonometric concepts is a plus, but all necessary trig functions will be explained during the class. If a transformer ratio is 201, then which of the following is true.
Ohms law is very helpful to help us understand sizing electrical circuits for the home electrical system. Much has to be learned to fully understand electrical theory, and it takes years to master. The handbook contains a wide array of topics and each topic is written by an authority on the subject. Either theory can be used as long as the orientations are correct. Finding motor hp horse power, kva kilovolt ampere kw input, when motor hp is known.
Engineers mininotebook formulas, tables and basic circuits author. Alternating current alternating or to find singlephase threephase to find direct current amperes when hp x 746 hp x 746 amperes when voltage and e. Electric current is the time rate of change of charge flow. So input kw to motor is out put efficiency of motor.
Volt unit of electrical potential or motive force potential is required to send one ampere of current through one ohm of resistance. Electrical formulas conversion formulas area of circle. Here i discuss some of important electrical formulas. Additionally, detailed charts and explanations that are sharply focused on the needs of the electrician and inspector make up the balance of the text. Dear viewer, especially for you, here is the free download of electrical formulas, theorems, definitions, laws, connections, symbols, circuits, units, equations pdf special reference copy. Active power is the resistive power and equals the equivalent heating effect on water. The modules listed in the overview are linked to the corresponding pages. Ohm unit of resistance one ohm is the resistance offered to the passage of one ampere when impelled by one volt. If the circuit components are connected end to end to form a single loop it is a seriescircuit.
The transfer function of an lti system may be defined as the ratio of laplace transform of output to laplace transform of input under the assumption ys gs xs. To convert a number which includes the k prefix to units, multiply the number preceding the k by 1,000. Understand the electrical principles of direct cur rent dc. Formulae for calculating amperes, horsepower, kilowatts.
As your studies continue, youll find that a good foundation in electrical theory and math will help you understand why the nec contains certain provisions. This theory states that electrons flow from negative to positive. Press the ohms law button after you have made your entries. The handbook includes information on alternating current ac and direct current dc theory, circuits, motors, and generators. Ohms law formulas for ac circuits and power factor. Engineers mininotebook formulas, tables and basic circuits led current led voltage drop forrest m. In order to construct a building that will last into the future, a strong foundation is a prerequisite.
User manual guide for electrical engineering formulas at file name. Electricity formulas are applied in calculating the unknown electrical parameters from the known in electric circuits solved examples. Complete electrical formulas sheet electrical engineering. We can find the following quantities by using below formulas chart electrical formulas in dc full load current in amperes alternating current ac motors alternating current ac single. Scrapbooking digital cards greeting cards, wedding invites, birthday cards. Know how to use ohms law in basic circuit calculations. The primary voltage is 20 times greater than that of the secondary. In electrical formulas and equations, you will see voltage symbolized with a capital e, while on laboratory equipment or schematic diagrams, the voltage is often. For every 20 turns in the primary, there is one turn in the secondary. Most state electrical exams include questions on general electrical theory. I amperes e volts kw kilowatts kva kilo voltamperes hp horsepower %. The theoretical foundation for ee is electromagnetism.
Useful electrical formulas to obtain single phase three phase kilowatts v x i x pf 1. V s supplied voltage or total voltage across impedance network. Bens theory became the convention hence the term conventional current in electrical theory, mathematics, textbooks and electrical equipment for the next hundred years. Formulae for calculating amperes, horsepower, kilowatts, and. This law basically states that current into a node will equal the current out of the node.
The teaching of basic science often involves what are known as lies to children, and. When we see a value such as 10 volts, it is a measurement of the potential difference between two. Electrical formulas tm electrical formulas to obtain. Understand the requirements of electrical circuit computations. Full load current in amperes alternating current ac motors alternating current ac single. Never connect any component or lead to electrical outlets in any way. This current varying in parallel circuits brought about kirchoffs next big law in basic electrical engineering, kirchoffs current law kcl. Hundreds of electrical products and tools to select from. Legend single phase ac three phase ac kilowatts v volts, i amperes, pf power factor vxixpf 1. The transfer function is completely specified in terms of its poles and zeros and the gain factor. Select the second icon down arrow available on the top right on the download page to get the file save to your desktop and smart phone. The handbook of electric power calculationsprovides detailed stepbystep calculation procedures commonly encountered in electrical engineering.
In other words, it is a measurement of the work required to move a unit charge between two points. Text headings in each module are linked to and from the table of contents for that module. Professor, electrical engineering, university of illinois at. Every effort is taken in order to maintain accuracy in the information contained within this web site. Ampere units of current one ampere is the current which one volt can. Twelve formulas can be derived from the preceding laws, as shown here. This portable document format \ pdf \ file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. Scrapbooking digital cards greeting cards, wedding invites, birthday cards printed paper products stationery. Fundamentals of electricity despite the fact that it has been positively determined that electron flow is the correct theory, the conventional flow theory still dominates the industry. Conventional flow will be used from this point on in these training modules unless otherwise. Includes calculations as applied to alternating and direct current. Text headings in each module are linked to and f\ rom the table of contents for that module.
A division of tandy corporation fort worth, tx 76102 rad. It is only applicable when the resistance network is connected in a parallel combination. Unit 1 electricians math and basic electrical formulas unit 2 electrical circuits unit 3 understanding alternating current unit 4 motors and transformers note. If the greek symbols for alpha beta delta do not appear here a b d the symbol font needs to be installed for correct display of notation and formulae c e e g i i k l m n p. Ohms law calculator voltsvoltage, ampscurrent, ohmsresistance, wattspower give me any two numeric values and ill give you all four.