Over sizing systems cost more and does not maintain the desired air flow and undersized duct work causes the system to strain mechanically and can be noisy. Jul 17, 2017 duct work that is an incorrect size can cause unnecessary noise, increased energy costs and lower air quality. To supply such systems, the bus duct manufacturer had to know where the duct penetrated fire separations required to have a fireresistance rating. This manual will be divided into several sections each section pertaining to a specific line of bus duct com plete with all of the dimensions, voltage drop curves, and characteristics. Residential main supply trunk ducts, nonzoned systems. Busbars have a compact design through which compressed flat. This appendix presents standards and guidelines for electrical design calculations for spu projects. Thus, by using the above formula and table, we can easily select. Sizing of air duct can be done using velocity method, constant pressure loss method and static pressure recovery method. Pdf energy resources management dictates the reduction of losses in electrical. It calculates the right airflow volumes and duct sizes for your system. A very approximate method of estimating the current carrying capacity of a copper busbar is to assume a current density of 2 amm2 1250 ain2 in still air.
A bus bar also spelled busbar, buss bar or busbar, is a strip or bar of copper. Electrical calculations should be made for all spu projects. Download free mep calculation excel sheets, autocad drawings, and training courses for hvac, firefighting, plumbing and electrical systems design. Duct sizing calculator software free download duct sizing. This free ductulator calculates the exact duct size round and rectangular for the given friction rate, duct type, and amount of airflow. Copper development association materials for busbar systems high electrical conductivity only silver is better than copper good thermal conductor heat reaches surface quickly. Apr 19, 2018 in this, we have shown earth bus bar, copper bus bar, aluminium bus bar and copper with tin coated bus bar current carrying capacity free electrical calculat. The velocity reduction method can be used when sizing air ducts. When it comes to sizing ductwork, you probably rely on a ductulator or its digital equivalent to determine the dimensions for your ducts. In electric power distribution, a bus duct also called busway, is a sheet metal duct containing either copper or aluminium busbars for the purpose of conducting a substantial current of electricity. Cfm and sizing calculations design master software. Duct systems distribute air from a heater or air conditioner throughout a home. Optimal ratings are achieved when the bar runs horizontally with the face of the bar in the vertical plane.
Download ductulator software for hvac duct sizing for free. Busbar design thermal conductivity electrical resistance. Laminated bus bars provide a low inductance connection for capacitors. Equivalent diameter is the diameter of a circular duct with similar. Duct work that is an incorrect size can cause unnecessary noise, increased energy costs and lower air quality. Generally, the velocity should be no more than 700 fpm. Panel design calculate size of bus bar excel electrical notes. It is used for sizing supply and return duct systems using the equal friction or equal velocity design methods. This equalfriction method of duct sizing should be adequate for normal residential furnace heating and air conditioning applications. Heat conduction and thermal resistance for steady state conditions and one dimensional heat transfer, the heat q conducted through a plane wall is given by. Turn to design master hvac for your complete hvac design and drafting solution. Find the sizes of main and branch ducts from the air flow rates and the velocities by using.
Features include 2d and 3d ductwork drafting, ductwork sizing, pressure drop calculations, and building load calculations. Design calculations establish minimum guidelines and requirements for generating electrical calculations on projects. Select suitable velocities for main and branch ducts from the table below. Busduct is a system of distributing electric power using copper or aluminium. Refer to uangyihtech flanges system section for adapters, drains and test port aw end available. Ductwork sizing, calculation and design for efficiency youtube. Include many heat exchanger models for detailed structure design or sizing calculation, such as coils and. At the pullout, the pulling rope exits the duct directly to a pulling sheave. Duct sizing and calculation methods revit products 2018. Hvac tools program allows the quick calculation of common hvac design tasks. Duct designer streamlines duct design and improves calculation precision, letting you optimize your designs. Duct calculator is a powerful tool that provides access to duct calculation and sizing capabilities either.
Consequently, the total pressure or total energy of air flowing in a duct system is generally equal to the sum of the static pressure and the velocity pressure. The table below can be used to compare equivalent diameters for rectangular and round circular ducts, ductwork sizing, friction loss, sheet metal gauges, etc. You need to determine the faul level of the systems and full load current from the customer to determine the cb rating. Copper for busbars guidance for design and installation. Includes a full worked example as well as using cfd simulations to. Duct sizing in revit, air density, air dynamic viscosity, and air flow are used to calculate duct sizing.
Southwires comprehensive product catalog provides additional data on cable weights, dimensions, and specifications to be used in concert with this guide. Abus duct system is an effective method of distributing power to your switchgear and various loads. In this, we have shown earth bus bar, copper bus bar, aluminium bus bar and copper with tin coated bus bar current carrying capacity free electrical calculat. Fibrous glass insulated hvac duct systems 4 sheet metal ducts with exterior fibrous glass exterior insulation flexible blanket fibrous glass duct wrap insulation is designed for application to the exteriors of commercial and residential sheet metal heating, ventilating, and airconditioning ducts and plenums operating at temperatures between 40. Bus bar size and voltage drop calculation tool eloquens. Lowvelocity ductwork design is very important for energy efficiency in air distribution systems. Design phase % load facility, switchgear, mcc load at each load center per nec to determine bus. Determining the usable crosssection of the bars the required crosssection of the bars is determined according to the operating current, the protection.
Highvelocity hv duct systems are characterized by air velocities in the range of 2500 to 3500 fpm. Designed to work like those conventional cardboard duct calculators that hvac engineers are so familiar with. It will automatically adjust the size to keep from exceeding the maximum manual d velocities for residential duct systems. Duct crosssectional area, air flow rate and air speed are used in calculating the duct size. Duct sizing calculator software free download duct. Ductsize lets you create a complete duct system from start to finish, and gives you control over every aspect of the design. Jan 03, 2007 great 4 deal 4 u is a blog for young engineer to get their free software program and guideline to design construction industries in building services either low voltage or extra low voltage great 4 deal 4 u. The main busbar and branch busbars supply and distribute the energy.
It will automatically adjust the size to keep from exceeding the maximum manual d velocities for residential duct. Pdf recent progresses in busducts design researchgate. Manual j residential load calculation eighth edition. Can u pl explain to calculate current rating of bus bar.
Paying attention to certain details of bus duct projects will ensure trouble free service. Jun 09, 2017 to this point in our little series on duct design, weve been calculating intermediate quantitites. Duct sizing and construction tables according to smacna pdf. These tasks include duct sizing, wire sizing, three way coil interpolation, mixed air and state point psychrometrics, fan curve and cost analysis, ufactor calculations, natural gas pipe sizing, refrigeration line sizing, general pipe sizing, hotchilled water pipe analysis.
David chapman copper development association david. Velocity duct sizing chart residential main supply trunk ducts, nonzoned systems target velocity of 800fpm used listed by air quantity, round duct size and nearest square duct size 500cfm 11o or 10 x 10 1,300cfm 16o or 14 x 16 600cfm 12o or 10 x 12 1,400cfm 18o or 16 x 16. Copper bar ampacity charts bus bar sizing calculator. Yet, bus duct problems lead to catastrophic damage and extensive downtime. Busduct modeling techniques are introduced which can be easily applied for busducts design. Were following the manual d protocol for duct design, a standard developed by the air conditioning contractors of america acca. Electromagnetic field distribution, thermal pattern inside and outside of the bus duct in normal. Ampacity charts for sizing copper bus bar with allowable temperature rise. You can then calculate bus bar rating based on the total connected load supplied by the bus bar and rate you bus bar. A halogenfree insulating plastic coating is extruded onto the bars. If the velocity in the duct is too high, the negative consequences can be excessive noise, duct movement from turbulent air rapid pressure fluctuations and ultimately, reduced longevity. Bus duct modeling techniques are introduced which can be easily applied for bus ducts design. The power dissipated by the bus bar is dependent on the square of the current passing through it, its length, and the material from which it is made.
Duct sizing needs a ductulator or software but this excel. The elite software hvac tools program allows the quick calculation of. There must be free air circulation around all of the bar in. Busbar design free download as powerpoint presentation. This method should only be used to estimate a likely size of busbar, the final size being chosen after consideration has been given to the calculation methods. Electromagnetic field distribution, thermal pattern inside and outside of the busduct in normal. A halogen free insulating plastic coating is extruded onto the bars. Powerful tool for thermal system as air conditioning system, refrigerating cooling system design. It is generally a hollow or flat piece of brass, copper, or aluminium.
Calculate voltage drop for bus bar, select size of bus bar for particular load, enter your sub panel details like load,line length. In this new edition the calculation of currentcarrying capacity has been greatly simplified by the provision of exact formulae for some common busbar configurations and graphical methods for others. Online ducting calculator to find the diameter of duct size. It is an alternative means of conducting electricity to power cables or cable bus originally a busway consisted of bare copper conductors supported on inorganic insulators. Lowvelocity design will lead to larger duct sizes, but it may be worth since, doubling of duct diameter. Figure f1 pulling cable in duct 1 ieee 5321993 guide for selecting and testing jackets for underground cables. Mdy busduct system a reliable and safe solution for power. Paying attention to certain details of bus duct projects will ensure troublefree service. The following duct sizes are based on a fraction drop of. Free ductwork tables for sizing and construction of hvac air ducts. Calculate size of bus bar having following details bus bar current details. Download hvac duct construction tables according to smacna and rule of thumbs pdf.
Today we use all that to find out how big the ducts need to be. Larger volumes or higher static pressures should be dealt with on an individual job basis. The ductulator is a simple program for air duct sizing. The assembly was designed for an automated production process and the. Whether using a friction chart or duct calculator, always check the velocity on the friction chart or duct calculator. Pressure drop calculation revit computes pressure losses in ductwork based on the geometry and roughness of the ductwork, air density, and air dynamic viscosity. To this point in our little series on duct design, weve been calculating intermediate quantitites. The velocity reduction method can be used for sizing air ducts. Duct sizing calculation software free download duct. We recommend sizing fabric ducts and diffusers by velocity or the air speed in the duct.
Design best practices for metal systems upstream of textile diffusers should. Before calculating the appropriate duct size, individuals will need to determine the required cubic feet per minute for a given room. Includes a full worked example as well as using cfd simulations to optimise the. Design master hvac is an integrated hvac building design and drafting program for autocad. A bus bar is a strip of metal that is used to conduct electricity within a distribution board, electrical substation, electric switchboard, and other electrical equipment. This guide includes many tables, equations, and related data for the convenience of the user. There is a gener al application section that applies to all types. Another important factor in the installation process is to make sure the duct work is sized properly. Quick busbar selector knowing the ampacity, designers and estimators can get the approximate bus bar size. Generally, it is preferred to distribute electrical energy by busducts in the place of cables. It is designed for calculating and sizing duct dimensions according to air volume cfm, roughness, velocity, etc.
In this video well be learning how to size and design a ductwork for efficiency. Sizing busbars the busbar constitutes the real backbone of any distribution assembly. For sizing either the trunks or branches simply align the friction rate with the cfm and the duct size will be displayed note. Oct 27, 20 a very approximate method of estimating the current carrying capacity of a copper busbar is to assume a current density of 2 amm2 1250 ain2 in still air. Rated voltage 415v,50hz, desire maximum current rating of bus bar 630amp.
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