The modules listed in the overview are linked to the corresponding pages. Legend single phase ac three phase ac kilowatts v volts, i amperes, pf power factor vxixpf 1. I hope it can make your basic understanding about electrical calculation is clear. Ampere units of current one ampere is the current which one volt can. This law basically states that current into a node will equal the current out of the node. Ohms law is very helpful to help us understand sizing electrical circuits for the home electrical system. 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. In other words, the net current in a node is zero or 0 i in i out. Understand the electrical principles of alternating current ac. The treatment throughout the handbook is practical with very little emphasis on theory. Electricity formulas are applied in calculating the unknown electrical parameters from the known in electric circuits solved examples. The teaching of basic science often involves what are known as lies to children, and. Know how to use ohms law in basic circuit calculations. The symbol font is used for some notation and formulae.
Electrical theory, alternating current, direct current, basic electrical theory, mike holt electrical theory books, videos and libraries. The handbook includes information on alternating current ac and direct current dc theory, circuits, motors, and generators. Electrical formulas conversion formulas area of circle. Ohms law formula and how it is used for determining electrical loads as it pertains to watts, volts and amps. Familiarity with trigonometric concepts is a plus, but all necessary trig functions will be explained during the class. Volt unit of electrical potential or motive force potential is required to send one ampere of current through one ohm of resistance. Finding motor hp horse power, kva kilovolt ampere kw input, when motor hp is known kw kilowatts amperes, when kva is known.
The letter k is used in the electrical trade to abbreviate the metric prefix kilo, which represents a value of 1,000. The primary voltage is 20 times greater than that of the secondary. Click on the doe seal below to move to the overview. It is only applicable when the resistance network is connected in a parallel combination. 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. This portable document format pdf file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. Ohms law formulas for ac circuits and power factor. Includes calculations as applied to alternating and direct current.
For every 20 turns in the primary, there is one turn in the secondary. Most state electrical exams include questions on general electrical theory. Finding motor hp horse power, kva kilovolt ampere kw input, when motor hp is known. Understand the requirements and configurations of electrical circuits. Journeyman electrician theory quiz 10 electrician exams. Chapter 1 advanced electrical theory seabee magazine.
An electrical distributor supplying everything from light bulbs and dimmers to plcs and industrial automation equipment. Formulae for calculating amperes, horsepower, kilowatts. Engineers mininotebook formulas, tables and basic circuits. Formulae for calculating amperes, horsepower, kilowatts, and.
When we see a value such as 10 volts, it is a measurement of the potential difference between two. Engineers mininotebook formulas, tables and basic circuits led current led voltage drop forrest m. 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. If a transformer ratio is 201, then which of the following is true.
Either theory can be used as long as the orientations are correct. Professor, electrical engineering, university of illinois at. Course syllabus elpt 11 basic electrical theory c a ta l o g d e s c r i p ti o n. 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. However, the author of this site shall not be held liable for the use of the information or of its consequences. 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.
For every 20 rotations in the secondary, there is one rotation in the primary. 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. The handbook contains a wide array of topics and each topic is written by an authority on the subject. Understand the requirements of electrical circuit computations. Electrical formulas, theorems, definitions, laws, connections. User manual guide for electrical engineering formulas at file name. This theory states that electrons flow from negative to positive. Useful electrical formulas to obtain single phase three phase kilowatts v x i x pf 1.
Electrical circuit calculations series circuits many circuits have more than one conversion device in them i. Active power is the resistive power and equals the equivalent heating effect on water. Common electrical units used in formulas and equations are. The transfer function is completely specified in terms of its poles and zeros and the gain factor. In series combination, the current remains the same through the resistance network. 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. To convert a number which includes the k prefix to units, multiply the number preceding the k by 1,000. A division of tandy corporation fort worth, tx 76102 rad. Never connect any component or lead to electrical outlets in any way. Basic electrical theory assessment exam proprofs quiz. Complete electrical formulas sheet electrical engineering.
Electrical formulas tm electrical formulas to obtain. 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. Electronic formulas ohms law formulas for dc circuits. Hundreds of electrical products and tools to select from. All this formulas are useful for basic calculation in electrical engineering including voltage,ampere,power, efficiency,power factor and many more. In other words, it is a measurement of the work required to move a unit charge between two points. Here i discuss some of important electrical formulas. Ohms law calculator voltsvoltage, ampscurrent, ohmsresistance, wattspower give me any two numeric values and ill give you all four. This portable document format \ pdf \ file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. Example 1 determine the current flowing through the electric heater have p.
Bens theory became the convention hence the term conventional current in electrical theory, mathematics, textbooks and electrical equipment for the next hundred years. Ohm unit of resistance one ohm is the resistance offered to the passage of one ampere when impelled by one volt. Electrical charts, tables and formulas musco engineering. Every effort is taken in order to maintain accuracy in the information contained within this web site. V s supplied voltage or total voltage across impedance network. The theoretical foundation for ee is electromagnetism. Electric current is the time rate of change of charge flow.
Full load current in amperes alternating current ac motors alternating current ac single. This current varying in parallel circuits brought about kirchoffs next big law in basic electrical engineering, kirchoffs current law kcl. The v is for voltage, which means the potential difference between two charges. 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. In the above formulas 1 is the angle of lead or lag between current and voltage and cos 1 pei power factor or pf. Engineers mininotebook formulas, tables and basic circuits author. Much has to be learned to fully understand electrical theory, and it takes years to master. 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. Unit 1 electricians math and basic electrical formulas unit 2 electrical circuits unit 3 understanding alternating current unit 4 motors and transformers note. Understand the electrical principles of direct cur rent dc. These formulas are carefully explained and demonstrated throughout the book. A basic understanding of electrical theory is important in order to understand your job as a construction electrician.
The most fundamental law in electricity is ohms law or vir. In order to construct a building that will last into the future, a strong foundation is a prerequisite. 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. Twelve formulas can be derived from the preceding laws, as shown here. The unit of energy is the joule, the unit of power is the watt, and the unit of time is the second. The handbook of electric power calculationsprovides detailed stepbystep calculation procedures commonly encountered in electrical engineering. Electrical theory alternating current direct current. 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. 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. So current amp of motor kw voltage 1 ph or kw sqrt3voltage pf 3 ph. Use the chart in this calculation guide to find the formula you need according to the measure you will calculate.
So input kw to motor is out put efficiency of motor. I amperes e volts kw kilowatts kva kilo voltamperes hp horsepower %. Finding motor hp horse power, kva kilovolt ampere kw input, when motor hp is known kw kilowatts amperes, when kva is. Scrapbooking digital cards greeting cards, wedding invites, birthday cards printed paper products stationery. If the circuit components are connected end to end to form a single loop it is a seriescircuit. Text headings in each module are linked to and f\ rom the table of contents for that module. Three phase formulas do not use 2 for threewire, two phase circuits, the current in the common conductor is 1. 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. Text headings in each module are linked to and from the table of contents for that module. 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. Press the ohms law button after you have made your entries. Conventional flow will be used from this point on in these training modules unless otherwise. Scrapbooking digital cards greeting cards, wedding invites, birthday cards.