These rules do not determine the magnitude but instead show the direction of any of the three parameters magnetic field, current, force when the direction of the other two parameters is known. Thumb rule to calculate the steel quantity required for slab, beams, footings. Thumb rules help you in finding out the solution using a simple mathematical formula and make smart decisions whenever needed. Chart 1 wire ampacity for short wiring runs ampacity is an abbreviation for ampere capacity. Righthand ruleelectromotive force produced by change of flux link. Electrical thumb rules you must follow part 4 on photo. While every effort has been made to ensure the accuracy of this information, errors can occur. Design examples with stepbystep solutions, along with a generous amount of tables, schematics, and calculations are provided. This is thumb rules so there is no any formulareferencescode for that this is used for.
Design calculations may be made either manually or by spuapproved computer programs. As such, neither flodraulic, any of its affiliated companies nor its employees will assume any liability for damage, injury or misapplication as result. Electrical thumb rule high rise building as per nbcwith 2 comments. Formulas and rule of thumb for electrical calculations. Thumb rules used in the construction by civil engineering. It covers preliminary load estimating factors and electrical power sources. There are endless thumb rule used in construction industry, i am stating few of them listed below. What are some of the rules of thumb of construction field. Flemings lefthand rule for electric motors is one of a pair of visual mnemonics, the other being flemings righthand rule for generators. Load factor average power peak power, demand factor, sinusoidal current.
Luminous efficacy, lumen maintenance and color rendition table8 nbc light source wattage efficacy lmw average life maintenance color rendition incandescent lamps 15 to 200 12 to 20 500 to fair to good very good tungsten halogen 300 to 1500 20 to 27 200 to 2000 good to very good very good standard. Design calculations establish minimum guidelines and requirements for generating electrical calculations on projects. Hvac rule of thumb calculator engineering pro guides. Rule of thumb if circuit is loaded up to ampacity and distance to load is around 100 feet, then voltage drop will govern and will require larger wire size. Using the whole number 7 is easier on the arithmetic and also covers some of the waste. But i use 7 bricks per square foot when calculating a brick count. Curl fingers to the direction of the magnetic field thumb points in the direction of the force. Electrical calculations should be made for all spu projects that include electrical components and should be filed in the project notebook.
Rules of thumb in engineering practice wiley online books. Flemings left hand rule and flemings right hand rule. These tips clear up the confusion and help you pass an electrical inspection. Top 10 thumb rule for electrical engineers for free 2017in this video you can learn top 10 thumb rule for electrical engineers subscribe to hotel engineering. Introduction to electrical power requirements for buildings. In thumb rules, the units are not the same when we compare to get the results. Featured products three right hand rules of electromagnetism teaching electricity and magnetism is complicated by the challenge that the magnetic forces are perpendicular to the motion of the particles and currents. Rule of thumb if circuit is loaded up to ampacity and distance to load is around 100 feet, then voltage. The thumb represents the direction of thrust on the conductor force on the conductor. Electrical thumb rules you must follow part 1 electrical thumb rules for. For lefthanded coordinates the left thumb points along the z axis in the positive.
Construction engineering calculations and rules of thumb begins with a brief, but rigorous, introduction to the mathematics behind the equations that is followed by selfcontained chapters concerning applications for all aspects of construction engineering. Qualification of officers appointed to assist the inspectors 5. Technical data bank of electrical engineering one key site to answer the queries of electrical engineers, technicians and students for study, design and maintenance of electrical equipments. Thumb rules only people, dont start posting nec rules please. Chilled water system, boiler system or electric heat, specialty systems dedicated outside air, chilled beams, etc. Point the thumb in the direction of motion of the conductor rela tive to the field. Professor and chairman of department of electrical engineering. Flemings lefthand rule is mainly applicable to electric motors and flemings righthand rule is mainly applicable to electric generators. Central plant systems plumbing and w ater use building control systems electrical power systems metering lanl. Selection guide for electric wire size womack machine. Three right hand rules of electromagnetism arbor scientific. They are only typical values, which should be verified for each application. Never use metal ladders around exposed electrical wiring. Blackburn, pe, mba course content course introduction.
Metal ladders should be marked with tags or stickers reading cautiondo not use around electrical equipment or similar wording. This chart is for short wiring runs of less than 20 feet. They were originated by john ambrose fleming, in the late 19th century, as a simple way of working out the direction of motion in an electric motor, or the direction of electric current in an electric generator. Understand what impacts the core design and rules of thumb to. This information is provided as a quick reference resource and is not intended to serve as a substitute for qualified engineering assistance. General rules of thumb for mid level estimates pe 0.
This requires a threedimensional perspective which can. For the love of physics walter lewin may 16, 2011 duration. Estimating topics for today order of magnitude mechanical. These rules of thumb are the result of preserving and structuring the immense knowledge of experienced engineers collected and compiled by the author an experienced engineer himself into an invaluable book that helps younger engineers find their way from symptoms to causes. Rule of thumb for datapath clock generator selection zongjian chen ee371 lecture 10 22 inductive noise prevention inductive noise can be an issue on low r top level wire delay and crosstalk show dependence on inductance when cload electrical codes diyers and pros mess up most often. See more of thumb rules for electricians on facebook. Order of magnitude mechanical estimating justin apprill, p. A rule of thumb is to design the wiring of sufficient size so the voltage drop will not exceed 5% of the input voltage. A discussion of the guiding principles and procedures governing project cost estimating. Electrical calculations is the best app in the electrical sector, it has many calculations that can help you in your work. Many problems stem from new additions to the national electrical code nec, while some common mistakes violate codes that have been on the books for years. Contents show thumb rule to calculate the concrete volume with respect to area. He is member of institution of engineers mie,india. If you have multiple floors, then add up all the air conditioned area for all floors and insert a single number for the hvac building area value.
You point the thumb of your right hand in a certain direction, and let the other fingers of your hand curl in the natural direction. Electrical thumb rulesilluminationpart20 quick referencefire fighting part2 quick referencefire fighting part1 internal electrical work abstract of cpwd. Electric service these standard rules and regulations and rate schedules contained herein have been adopted by the cooperative to govern its relations with memberconsumers and have been approved by the board of directors of thumb electric cooperative as an integral part of its rate book for electric. Typical hvac rules of thumb abraxas energy consulting.
Cost estimating fundamentals and tricks of the trade. Rule 1 is for determining the direction of the magnetic field produced by a currentft. Right hand rule for magnetic field due to a straight wire to find the direction of the magnetic field use the. In order to construct a building that will last into the future, a strong foundation is a prerequisite. How to calculate cable sizes for the below in thumb rule, 01. Equipment utilize rule of thumb or actual cost from vendors.
A manual of quick, accurate solutions to every day mechanical engineering problems. Distribution substation bus on a clear night in february by eli nelson, via flickr. For large substation roomelectrical room having multiple equipment, two or more doors shall be provided. Also, if youre interested in learning even more, heres a free download for you. Whether youre concerned with design, selection, or performance, youll find fast, accurate answers.
Electrical thumb rules technical data bank of electrical. In mathematics and physics, the righthand rule is a common mnemonic for understanding. Thumb rules for civil engineers and basic knowledge. An accumulation of charges is what we call voltage. Substation capacity and short circuit current capacity as per gerc substation capacity and short circuit current capacity as per central electricity authority minimum ground clearance and fault clearing time. Appointment of officers to assist the inspectors 4b. Before specific electric power sources and distribution systems can be considered, realistic preliminary load data must be compiled.
This is thumb rules so there is no any formulareferencescode for that. Cost estimating and tricks of the trade a practical approach timothy d. Construction engineering design calculations and rules of. Electrical engineeringportal com electrical thumb rules you must follow part 5. If the overhead power line is 50 kv or less, then stay at least 10 feet away. Electric power loads shall include all loads other. Electrical thumb rules you must follow part 1 electricity. If a positive electric charge moves across a magnetic field it experiences a. Pdf electricalengineeringportal comelectrical thumb. Calculate size of cable for motor as nec how to design efficient street lightingpart6.
That means 3 bricks will cover 8x8 inch es, or 64 square inches, which translates to 6. Electric current in the circuit magnetic field electric current in the circuit m 3 fmt loop this righthand rule is different. Introduction to electrical power requirements for buildings course no. So never consider units while performing thumb rule. Electrical rooms 4,000 0 total 127,000 110,000 in the sample office building above, you would use the 110,000 ft2 value in the hvac rule of thumb calculator. But, while using these thumb rules, you must remember that the thumb rule never gives the exact or accurate results, you just have used them for approximate results.
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