Stamford PMG Systeem Permanente Magneet Generator

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Voor sommige toepassingen kan het magnetisch veld van de generator worden verstrekt door permanente magneten. De rotor structuur kan bestaan uit een ring van magnetisch ijzer met magneten gemonteerd op het oppervlak. Een magneet materiaal zoals neodymium-ijzer-boor-of samarium-kobalt kan een magnetische flux in de luchtspleet vergelijkbaar is met die geproduceerd met veld windingen, met behulp van een radiale diepte van magneet van minder dan 10 millimeter. Andere magneet materialen zoals ferriet kunnen worden gebruikt, maar met een aanzienlijke vermindering van lucht-gap fluxdichtheid en een overeenkomstige stijging van de generator dimensies. Permanente-magneet generatoren zijn eenvoudig omdat zij vereisen geen systeem voor de levering van de huidige veld. Ze zijn zeer betrouwbaar. Ze doen echter niet bevat geen middelen voor het regelen van de uitgangsspanning. Een typisch voorbeeld van het gebruik is met een windturbine waarbij de generator output van variabele spanning en frequentie wordt geleverd aan een macht systeem via een elektronische frequentie-omvormer.

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Mogelijkheden van het gebruik van auto Dynamo in Wind Turbines

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De meeste van hun tijd wind-generatoren draaien bij lage rotaties. Auto dynamo zou niet tot iets lagere snelheid van windturbines. Daarom is met behulp van een auto dynamo in windgenerator is echt een slechte optie.

• De efficiëntie van de alternator zou nooit meer bereiken dan ongeveer 60%. De lagers zijn erg klein en kan niet instemmen met grote bladen betrouwbaar (ongeveer 1,5 meter diameter). De auto alternator is ontworpen als lichtgewicht en robuuste wordt de werking ervan bij zeer hoge toeren.
  

• Hoewel een klein mes kan worden gebruikt om de alternator spin maken bij hoge toeren. Maar kleinere bladen zou vangen minder wind. Je zou moeten een hoge windsnelheid te verkrijgen noodzakelijke snelheid van de rotatie.

• Gears met katrollen of andere methoden kunnen worden gebruikt om te stimuleren tpm. Maar veel van de macht wordt verspild door wrijving. Dit zou resulteren in extra kosten, verdere verliezen, toegevoegd onbetrouwbaarheid, en een vreselijk en onhandig gemaakt project.

 

• Er is een andere mogelijkheid terugspoelen van de alternator te draaien op lagere snelheid. Maar dit betekent ook dat er meer omwentelingen van dunne draad in elke spoel. Bij deze methode cut-in rotaties zijn gedaald, maar de verliezen in de spoelen zijn ook verhoogd, dus u zou krijgen verminderde vermogen en verdere vermindering van de reeds lage efficiëntie.

• Auto of vrachtwagen dynamo is een elektromagnetische apparaat. Het betekent dat gescheiden macht wordt vereist door de alternator naar het magnetisch veld te maken voor de elektromagnetische spoelen intern door middel van borstels en sleepringen.

Apture ™

Wind Turbine - spoelen diagram

Click Here for English Version of this Article

De alternator heeft twee 12 inch diameter rotors die elk 12 neodymium magneten schijf meet 1,47 inche in diameter en ,6 centimeter dik. Tussen de rotors is de stator bestaande uit 9 rollen van AWG # 20 draad, 200 omwentelingen per stuk. De spoelen zijn ingericht voor de productie van 3-fase ac.

Elke fase heeft 3 spoelen in serie geschakeld. Er zijn 3 volledig golf brug gelijkrichters, een voor elke fase. Ieder is geïsoleerd van de andere. Alle drie dc verholpen uitgangen met elkaar zijn verbonden parallel en het dc wordt verzonden via de kabel om de batterij bank.

De stator wordt gemaakt door sodat de spoelen tussen twee stukken van epoxy fiber glas boord, de soort gebruikt bij de vervaardiging van printplaten. De bovenste en onderste vel, elk 1 / 16 cm dik, worden bij elkaar gehouden met bouten. Ze hebben verstevigingsribben toegevoegd voor stijfheid. Power is gebracht door middel van roestvrij stalen schroeven machine.

Als u wilt er zelf een te bouwen, moet je weten het kan theoretisch 316W produceren, door de formule:

Watts = Conversie constante Betz limiet * * * efficiëntie gebied in vierkante m * wind ^ 3
In een perfect efficiënte turbine,
Watts = .05472 * 59% * 100% * 4,46 * 13 ^ 3 = 316 watt "

Circuit Diagram van Three Phase Alternator

Natuurlijk, dingen zijn verre van perfect, de jongens dat maakte deze zei dat ze kregen 70W eruit. That's pretty good! Maak een paar soortgelijke inrichtingen, zet ze op je blok en je zult nooit meer betalen voor elektriciteit weer! (meer of minder - afhankelijk van uw verbruik gewoonten). Hoe dan ook, als je woont in een gebied met hoge windsnelheden, kunnen deze apparaten kosten een 12V auto-batterijen, zodat ze je huis voor de ochtend en avond, als je terug bent van werk macht. Tijdens de nacht en de dag, accumuleren ze energie. De enige serieuze "permanente" consument zou uw koelkast.

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Homemade Winding Diagrams for Car Alternator

Understanding 3 phase alternators

Word "Phase" refers to the magnets passing over the coils at different times. There are two types of wirings for alternators:

• In single phase wiring, all the magnets and coils line up with each other.
• In 3 phase wiring, 2 extra coils slightly out of phase with first.

There is more detailed, complex but otherwise fine examples are available at

• http://www.windstuffnow.com/main/3_phase_basics.htm
• http://www.sawt.cn/News/HomeMadeWindTurbine/49.html
• http://samarium.vitatechindia.com/SamFolder/SamHelp/index.html?hm_current_in_wye_connected_motor.html

Car alternators are considered to be a poor choice for wind turbine. However, Car alternators can be used by rewinding a 12V car alternator. with modified  rotor with N42 magnets. But in this way you will get less volts than required at least 15 V at 300 rpm or even at lower speed. You need to get 5 times the number of turns on the stator with wire of a smaller gauge. Measure the diameter of the existing wire, calculate it's cross-sectional area, and find a wire 5-6 times smaller in area. That will reduce the current by the same factor.

Possibilities of Using Car Alternator in Wind Turbines

Most of their time wind generators rotate at low rotations. Car alternators would not generate anything at lower speed of wind turbines. Therefore, using a car alternator in wind generator is really a poor option.

• The efficiency of alternator would never reach more than about 60 %. The bearings are very small and can not support large blades reliably (about 1.5 meters diameter). The car alternator has been designed as lightweight and robust being its functioning at very high rpm.
• Although a small blade can be used to make the alternator spin at high rpm. But smaller blades would catch less wind. You would need a high wind speed to obtain necessary speed of rotation.
• Gears with pulleys or other methods can be used to boost rpm. But a lot of power is wasted through friction. This would result in additional cost, further losses, added unreliability, and a horribly and awkwardly made project.
• There is another possibility of rewinding the alternator to run at lower speed. But this also means that there would be more turns of thin wire in each coil. In this method cut-in rotations are decreased, but losses in the coils are also increased, thus you would get decreased power output and further reducing the already low efficiency.
• Car or truck alternator is an electromagnetic device. It means that separate power is required by the alternator to make the magnetic field for its electromagnetic coils internally through brushes and slip rings.

Homemade Magnetically Levitated VAWT

This design allows you construct a Perfect Magnetically-Levitated VAWT from inexpensive components. Because this is a Mag-Lev it’s nearly almost smooth and frictionless and efficient.

Components required:

• Take 3 round plates of 0.5 inch thick plywood with 3 ft diameter with a hole of 2 inch diameter in the center
• Take 32 Neodynium disk magnets, N45 (Mark 16 magnets with red having North Pole and other 16 with South Pole with blue ink)
• Take 4 Neodynium Torus magnets, N45 (Mark 2 magnets with red having North Pole and other 2 with South Pole with blue ink)
• 32 small plastic coils of Copper 14 AWG enamel insulation wire
• 1 Steel pipe 4 Feet long and 2 inch diameter with mountable legs
• 16 plastic plates, 1 Foot by 3 Foot and 0.5 inch thick
• 64 small right-angle mounts
• 128 wood screws, 0.5 inches long phillips
• 1 metal lock-ring torus, 2 inch diameter hole in middle with screw in from side to fix to axle

See a video for learning to assemble them at the following link:-

Hydro-turbine Testing Verdant

Verdant Enters Second Phase of Hydro-turbine Testing

Verdant Power has an ambitious hydropower plan. The company was testing an underwater turbine in the East River in New York since 2002.

A number of research organizations and leading research institutions are working on such projects, which uses the motion of Water in the East River to turn underwater, propeller-type turbines that generate power.

Two $500,000 grants for the project were awarded to Verdant from the New York State Energy Research and Development Authority (NYSERDA). The total, three-stage project is estimated to cost $1.5 million, and NYSERDA is expected to continue supplying grants for the research and development phase.

The motion of the tides in the East River can reach 4 knots, and Verdant mounted axial flow turbines on the river bottom. First phase turbines had rotors with a 10-foot diameter, and they have been generating up to 16 kW of power. Second phase turbines have a 16-foot rotor diameter, and are designed to generate 35 kW of power. A yaw system allows the turbines to rotate on a vertical axis so they can capture energy from both the ebb and flow of the river tides.

Information gathered from the test should prove valuable to FERC in the future if Verdant decides to pursue a license for the technology. The facilities would be located in the East River off Roosevelt Island in Queens County, New York. The company's long-term proposed project would consist of 494 turbine generator units rated for 21 kW each.

Verdant Power expects to complete this $10 to 20 million East River project, including power conditioning and grid connection, by 2007. Subsequent sites will be developed in less than one year.

As the company enters into its second stage of testing they had to start thinking about the proper licensing for the power plant. Lucky for Verdant, the Federal Energy Regulatory Commission (FERC) is on board with the plan, and has ruled that the company can continue testing without a hydropower license.

Verdant is still required to obtain the necessary federal, state and local permits before moving ahead with the planned 18-month technology test.

winding low-power alternator stator

Process for making a winding for a low-power alternator stator - Patent 4449288:


A process making it possible to manufacture and locate a winding of an undulating shape, more especially for an alternator stator of a motor vehicle.

Initially externally of the stator and for each phase, a circular flat coil is formed having the desired number of turns. This coil is then preformed, still externally of the stator, so as to give it an undulating flat star shape, whose undulations correspond to the number of poles and notches of the stator. Then this preformed coil is moved against the bundle of sheets of the stator and wires are inserted into the notches by preforming a tilting action which deforms the coil out of its plane. The apparatus for practicing the process of insertion by tilting particularly comprises a mandrel, which is introduced into the bundle of sheets along the axis of the stator.

Micro-Hydro Water Turbines for Home Power

Not everyone is lucky enough to have a source of running water near their homes. But for those with river-side homes or live-on boats, small water generators (micro-hydro turbines) are the most reliable source of renewable energy available. One relatively small water turbine will produce power non-stop, as long as running water is available, no matter what the weather.

We're pleased to introduce a comprehensive line of micro-hydro water turbines, including LVM's AquaGen and Ampair's Aquair UW submersible propeller turbines, Harris Pelton and Stream Engine impulse turbines, and a comprehensive line of small reaction turbines including the LH1000, Nautilus, Neptune, Niade and Power Pal micro-hydro power systems.

For people with a good source of year-round running water, one or two water turbines may be all they need to power their homes. However, for those with seasonal, winter-only streams available, a small water generator may be the perfect back up for a solar system's off-peak season.

If you think a home water power system may work for you, browse our site for more information, or contact us for help putting together a microhydro system to meet your needs.

Micro-Hydro Water Turbines for Home Power | Alternative & Renewable Energy - ABS Alaskan, Inc.

Osprey Turbine Exploit Sea River power

A small team of engineers in Cornwall has made a breakthrough with the development of a turbine that they claim could solve the commercial viability of tidal power.

The Osprey turbine can be used to create electricity offshore at sea or in tidal rivers and inland waterways. Following successful testing of a model rotor, a reduced-scale model prototype has been developed to assist in the design of a full-scale prototype.

Research and development consultants in renewable energy, FreeFlow 69, conceived the turbine concept while working on design and development work for its offshore Ocean Hydro Electricity Generator (OHEG), a concept using tidal energy to create electricity 24 hours a day.

The Osprey turbine is a vertical axis free flow device which produces power independently or as part of a larger system. Power output is expected to be from 1kW up to 5MW in a multiple system.

Parts for the prototype model were pre-fabricated in stainless steel by associate company Able Engineering of Swadlincote, Derbyshire and assembled in Fowey.

With the significant advantage that the gearbox and generator are above the water level, it operates effectively in variable depths to maximise the efficiency of the power available through the tidal cycle, or in differing river heights.

It is also environmentally friendly and will not interfere with marine or river life, can be mounted on the sea bed or suspended on pontoons, is bi-directional and will turn the same way in a flooding or ebbing tide.

Due to its modular design, a bank of Osprey turbines can be built up and added to in order to generate more power.

"We already have a patent application in place and plan to build a full size prototype by the Autumn," said Mr Cooke. "If this is successful, as we are confident it will be, we intend to manufacture a range of small units for river applications, followed by a range of cross flow turbines for conventional micro hydro plants."

A prototype for an Archimedes screw type version turbine will also be produced for rivers where a weir or leat is available, such as old mill sites.

Electromagnetics - Alternators Design

flat pack disc alternator


An alternator based on a disc design for easy assembly and disassembly. 24 magnets, 24 coils, 4 discs, 12 bolts, 12 nuts, an axle, a bearing. This design is based on similar designs for windmills.

Single Phase Parallel Winding High Amperage

Single Phase Series Winding High Voltage

Three Phase Parallel Winding High Amperage

Three Phase Series Winding High Voltage

Efficient wind turbine design for low velocity air flow

United States Patent 4427343 is a Efficient wind turbine design for low velocity air flow.
Abstract: Six rows of radial blades, arranged to extend in a spiral (in the direction of axial rotation) covering 55 degrees of arc about a hollow support section, constitute an optimum blade arrangement for maximum efficiency in low velocity airflows. Each blade in the rows is contoured to receive both direct flow pressure as well as airfoil lift in order to provide maximum energy transfers from low velocity airflows.

Wind Funnel Technology to Enhance Efficiency of Low Wind Turbines

The main complication of a Wind Funnel is to turn the entire thing into the wind. Bernoulli and his Physics are very useful in search of a ratio of mouth to throat area with acceptable air flow.

 

A small aerodynamically perfect wind turbine design is easy to build. The turbine would rotate fairly fast.

 

Wind Funnel Technology to Enhance Efficiency of Low Wind Turbines

The main complication of a Wind Funnel is to turn the entire thing into the
wind. Bernoulli and his Physics are very useful in search of a ratio of
mouth to throat area with acceptable air flow.

A small aerodynamically perfect wind turbine design is easy to build. The
turbine would rotate fairly fast.

Savonius Type Vertical Axis Wind Turbine

Two types of vertical axis wind turbines, Savonius and Darius, are mostly used. The Savonius wind turbine was invented by Sigrid Savonius of Finland. Although, the Savonius type of vertical axis windmill less efficient than a conventional design but it does not need to be kept in a single direction. With simple junk like oil drums, car alternator or dynamo, you can build wind generator. This is wind generator will charge 200 watts battery.

Characteristics of Savonius Wind Turbines

Savonius wind turbines are not needed to be installed on high towers and polarity or direction of the wind turbine does not change with the direction of wind and over the land surface and Roof-top installation is normally used. Materials and construction cost is much lower than horizontal axis wind turbines. Split a barrel into half and putting together these two vertically split halves to a vertical axis. This creates a low speed high torque unit that can be utilized for driving water and through a gearing mechanism, generate electricity.

This design works on "magnus principal", an aerodynamic effect. The most everywhere usage of the Savonius wind turbine is the Flettner Ventilator. It employs the design of Savonius wind turbine to drive an extractor fan.

Wind Turbine Alternator - Coils Diagram

Here is a DIY Project for wind turbine alternator.

The alternator has two 12 inch diameter rotors that each have 12 neodymium disk magnets measuring 1.47 inche in diameter and .6 inches thick. Between the rotors is the stator consisting of 9 coils of awg #20 wire, 200 turns each. The coils are arranged to produce 3-phase ac. Each phase has 3 coils wired in series. There are 3 full wave bridge rectifiers, one for each phase. Each is isolated from the other. All three rectified dc outputs are wired together in parallel and the dc is sent via cable to the battery bank.

The stator is made by sandwiching the coils between two pieces of epoxy fiber glass board, the kind used in the manufacture of printed circuit boards. The top and bottom sheets, each 1/16 inch thick, are held together with bolts. They have reinforcing ribs added for stiffness. Power is brought out by means of stainless steel machine screws.

If you’d like to build one yourself, you must know it can theoretically produce 316W, by the formula:

"Watts = Conversion constant * Betz limit * efficiency * area in sq. m * wind^3

In a perfectly efficient turbine,

Watts = .05472 * 59% * 100% * 4.46 * 13^3 =316 watts"

Circuit Diagram of Three Phase Alternator

Of course, things are far from perfect, the guys that made this said they got 70W out of it. That’s pretty good! Make a few similar devices, put them on your block and you’ll never pay for electricity again! (more or less - depending on your consumption habits). Anyway, if you live in an area with high winds, these devices can charge some 12V car batteries so they power your home for the morning and evening, when you get back from work. During the night and the day, they accumulate energy. The only serious "permanent" consumer would be your fridge.

Stamford PMG System (Permanent Magnet Generator) - China STAMFORD ALTERNATOR,STAMFORD PARTS,PMG SYSTEM in Power & Generating Sets

Stamford PMG System (Permanent Magnet Generator) - China STAMFORD ALTERNATOR,STAMFORD PARTS,PMG SYSTEM in Power & Generating Sets: "Stamford PMG System (Permanent Magnet Generator)
Stamford PMG System (Permanent Magnet Generator)
Stamford PMG System (Permanent Magnet Generator)

Product Description

We are a special company that service for generators and generator-sets. We can supply PMG system for STAMFORD brushless generators.

* Voltage: 170~220VAC
* Current: 3A / Phase
* Frequency: 100~120HZ nominal
* Phase: 3
* Wire: 3

Adapt to AVR type, STAMFORD MX341-2, MX321-2"

Permanent Magnet Alternators

Use these powerful permanent magnet alternators (PMA’s) to make cheap electricity from Wind, Hydro, Steam and Bio-Diesel power systems. Hornet permanent magnet alternators are by no means standard "Automotive" alternators containing brushes and electro-magnetic coils. A PMA does not waste power by having to continuously create an energy intensive magnetic field. Stop wasting up to 50% of your power energizing the coil of standard brush type alternators. Get a real PMA!

PMA Models:

Super Core PMA’s (For use with the Hornet 1000watt Turbine)
SC12
SC24
SC48
SC60
SC120

Slant Core PMA’s (For use with the Hornet 600watt Turbine)
SCS12
SCS24
SCS48

Permanent magnets frameless alternators for Direct Drive

The range of STK Permanent Magnet frameless alternators addresses the applications of Wind Turbine generators in low and medium power needing the highest power-to-weight ratio in Direct Drive without gear for matching cost-effective solutions.




Each component of a wind turbine generator and wind turbine alternator requires maximum strength and precision in order to ensure perfect control over the blades.

Technorati : Direct Drive, Permanent magnets, alternators, frameless

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Wind Research - International Wind Resource Maps

Here is a collection of access to NREL-developed wind resource maps and atlases for several countries. NREL also provides access to maps available from the Asia Alternative Energy Program (ASTAE) and the Solar and Wind Energy Resource Assessment (SWERA). The SWERA Link includes solar maps as well as the wind maps, GIS data, interactive maps, and country reports. Some of the following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

Maps Developed by NREL

Afghanistan: Map: Afghanistan (PDF 385 KB)

Armenia: Atlas: Elliott, D., Schwartz, M., Scott, G., Haymes, S., Heimiller, D., George, R. (July 2003). Wind Energy Resource Atlas of Armenia (PDF 8.9 MB). NREL/TP-500-33544.

Bhutan: Map: Bhutan (PDF 198 KB)

Central America: Maps: Central America (PDF 2.9 MB), El Salvador (PDF 366 KB), Guatemala (PDF 139 KB), Honduras (PDF 1.6 MB), Nicaragua (PDF 1.9 MB), Chile Maps: Region IX: Pacific Coast (PDF 135 KB), Region X: Pacific Coast (PDF 107 KB), Region X: Selected Islands - Isla de Chiloe Area (PDF 124 KB), Region X: Lago Ranco Area (PDF 111 KB)

China: Atlas: Elliott, D., Schwartz, M., Scott, G., Haymes, S., Heimiller, D., George, R. (November 2002). Wind Energy Resource Atlas of Southeast China (PDF 17 MB) The zip file contains the PDF plus additional data files referenced in the PDF (ZIP 23 MB). NREL/TP-500-32781.

Maps:

• Chifeng (PDF 1 MB)
• East China (PDF 4.3 MB)
• Enshi (PDF 390 KB)
• Fuzhou (PDF 2.6 MB)
• Guangzhou (PDF 970 KB)
• Haikou (PDF 1.3 MB)
• Hangzhou (PDF 2.3 MB)
• Hohhot (PDF 663 KB)
• Jiamusi (PDF 992 KB)
• Manzhouli (PDF 922 KB)
• Qingdao (PDF 1.5 MB)
• Qiqhar (PDF 672 KB)
• Shenyang (PDF 1.7 MB)
• Tianjin (PDF 1.8 MB)
• Yinchuan (PDF 769 KB)

Cuba: Map: Cuba (PDF 1.63 MB)

Dominican Republic: Atlas: Elliott, D., Schwartz, M., George, R., Haymes, S., Heimiller, D., Scott, G., Kline, J. (October 2001). Wind Energy Atlas of the Dominican Republic (PDF 14.37 MB). NREL/TP-500-27602.

Ghana: Map: Ghana (PDF 620 KB)

Indonesia: Maps: Sumba (PDF 80 KB), West Timor (PDF 86 KB)

Mexico: Atlas: Elliott, D.; Schwartz, M.; Scott, G.; Haymes, S.; Heimiller, D.; George, R. (August 2003). Wind Energy Resource Atlas of Oaxaca (PDF 15.6 MB)." NREL/TP-500-34519.

Maps:Baja California: Norte Border Region (JPEG 542 KB; PDF 367 KB), Western Chihuahua Border Region (JPEG 621 KB; PDF 950 KB), Northwestern Mexico Border Areas (JPEG 538 KB; PDF 726 KB), Eastern Sonora Border Region (JPEG 467 KB; PDF 342 KB), Western Sonora Border Region (JPEG 454 KB; PDF 599 KB), Baja California Sur (GIF 284 KB; PDF 506 KB), Quintana Roo and Yucatan (GIF 274 KB)

Mongolia:Atlas:Elliott, D., Schwartz, M., Scott, G., Haymes, S., Heimiller, D., George, R. (August 2001). Wind Energy Resource Atlas of Mongolia (PDF 24.48 MB). NREL/TP-500-28972.

Pakistan: Map: (PDF 388 KB)

Philippines:Atlas: Elliott, D., Schwartz, M, George, R. Haymes, S., Heimiller, D., Scott, G., McCarthy, E. (February 2001). Wind Energy Resource Atlas of the Philippines (PDF 14 MB). NREL/TP-500-26129.

Russia:Map: Murmansk and Arkhangel'sk (JPEG 920 KB)

Sri Lanka and the Maldives: Atlas: Elliott, D., Schwartz, M., Scott, G., Haymes, S., Heimiller, D., George, R. (August 2003). Wind Energy Resource Atlas of Sri Lanka and the Maldives (PDF 28.71 MB). NREL/TP-500-34518.

Other Links to Wind Resource Maps

Solar and Wind Energy Resource Assessment (SWERA)

The Solar and Wind Energy Resource Assessment (SWERA) provides information about solar and wind energy resources in thirteen partner countries around the world. Products include data on wind and solar energy potential, plus detailed country energy analyses. SWERA is a UNEP (United Nations Environment Programme) project with co-financing from Global Environment Facility (GEF). The goal is to provide solar and wind energy assessments to potential investors and the public to promote more effective use of alternative energy resources.

World Bank Group's Asia Alternative Energy Program (ASTAE)

Asia Alternative Energy Program (ASTAE) maintains the Wind Energy Resource Atlas of South Asia. The atlas covers four countries: Cambodia, Laos, Thailand, and Vietnam. The purpose of the atlas is to facilitate the development of wind energy both for utility-scale generation and for village power and other off-grid applications.

Volt-amperes to Watts Conversion Formula

 

Volts, Watts, AMPS, KVA, KW and Horse Power Conversions

It is not really a conversion as such but a formula where any two values are needed  to be known to enable the third to be calculated.

 

Convert Watts to Volts:

Voltage = Watts / AMPS

E = P ÷ I

 

Convert Watts to AMPS:

AMPS = Watts / Voltage

I = P ÷ E

 

Example:

2,300 WATTS = 2300w divided by 120v = 19.1 AMPS

(for 3 Phase divide by 1.73)

Convert AMPS to Watts:

Watts = Voltage x Amps

P = E x I

Example: 19.1 AMPS multiplied by 120v = 2300 Watts

(for 3 phase multiply by 1.73)

 

Convert Horse Power to AMPS:

HORSEPOWER= (V x A x EFF)÷746

EFFICIENCY= (746 x HP)÷(V x A)

Multiply Horse Power by 746w (1 HP = 746 Watts)

Find Circuit Voltage and Phase

 

Example:

30 HP at 480 (3 Phase) - 746 multiplied by 30 = 22380

22380 divided by 480 (3 Phase) = 46.5

46.5 divided by 1.73 = 29.5AMPS

Multiply all the motor loads by 1.50% and go to the next circuit size.

Convert KVA to AMPS:

Multiply KVA by 1000/voltage

Example:

30 KVA multiplied by 1000v = 30,000 Watts

30,000 Watts divided by 480 = 62.5 AMPS

(for 3 phase divide by 1.73)

 

Convert KW to AMPS:

Multiply KW by 1000/voltage and then by power factor

Example:

30KW multiplied by 1000v = 30,000

30,000 divided by 480 = 62.5 x .90 = 56.25amps

(for 3 phase divide by 1.73)

 

Symbolic

E =VOLTS or (V = VOLTS)

P =WATTS or (W = WATTS)

R = OHMS or (R = RESISTANCE)

I =AMPERES or (A = AMPERES)

HP = HORSEPOWER

PF = POWER FACTOR

kW = KILOWATTS

kWh = KILOWATT HOUR

VA = VOLT-AMPERES

kVA = KILOVOLT-AMPERES

C = CAPACITANCE

EFF = EFFICIENCY (expressed as a decimal)

Two-stage Evaporative Cooler

Getting out of a pool and standing in a breeze will help you feel cool, even on a hot day. This is the principle behind evaporative cooling. Evaporative coolers, often called "swamp coolers", are cooling systems that use only water and a blower to circulate air. In the system, warm, dry air is pulled through a water-soaked pad. As the water evaporates, a cooling effect on the surrounding air occurs. Evaporative coolers use only a fraction of the energy of traditional air conditioning systems. Unfortunately, except for in very dry climates, they may increase humidity to a level that makes occupants uncomfortable. Two-stage evaporative coolers do not produce humidity levels as high as that produced by traditional single-stage evaporative coolers.

In the first stage of a two-stage cooler, warm air is pre-cooled indirectly without adding humidity (by passing inside a heat exchanger that is cooled by evaporation on the outside). In the direct stage, the precooled air passes through a water-soaked pad and picks up humidity as it cools. Because the air supply to the second stage evaporator is pre-cooled, less humidity is added to the air (because cooler air can't hold as much moisture as warmer air). The result, according to the manufacturer, is cool air with a relative humidity between 50 and 70 percent, depending on the climate, compared to a traditional system that produces about 80 percent relative humidity air.

An advanced two-stage evaporative cooler uses 100 percent outdoor air and a variable speed blower to circulate cool air. Two-stage evaporative coolers can reduce energy consumption by 60 to 75 percent over conventional air conditioning systems, according to the American Society of Heating and Engineers (ASHRAE). Yet this relative improvement depends on location and application. Evaporative coolers work best in very dry climates and are not suitable for much of the East Coast, Midwest, and Coastal U.S.

sodium, potassium and magnesium chlorides as Thermal energy storage Medium

The thermal energy storage material of this invention is prepared by mixing sodium chloride, potassium chloride, and magnesium chloride in eutectic proportions. While the precise eutectic composition is most desirable because of the maximization of effectiveness of the salt mixture, an excellent energy-storage material is obtained from a salt mixture comprising from 22.5 to 26.5 weight percent of sodium chloride, from 18.5 to 22.5 weight percent of potassium chloride and from 53.0 to 57.0 weight percent of magnesium chloride.

Small quantities of one or more additional salts referred to as additive salts may be added to the salt mixture. These additive salts lower the melting point slightly, e.g , a small addition of a sulfate salt lowers the melting point from 385° C. to 380° C. The preferred salts are calcium, barium, or strontium cloride; sodium, potassium, or magnesium bromide, fluoride, or sulfate. The amount of these salts may be as high as 10 weight percent of the total composition.

The salts are at least 90 percent pure with no impurities which react with the chlorides, e.g., chromium oxide (CrO₃) or vanadium pentoxide (V₂ O₅). If additive salts are to be mixed with the ternary salt mixture, then it is preferred that the purity of the salts of the present invention be such that the final mixture comprises at least 90 weight percent of sodium chloride, potassium chloride, and magnesium chloride. Larger amounts of impurities would diminish the effectiveness of the salts. In order to minimize any corrosion problem, water and hydrogen chloride are expelled from the mixture. An excellent method for eliminating water and hydrogen chloride involves an initial melting and cooling of the salt mixture. While melted, the remaining hydrogen chloride or water is eliminated by the inclusion of strips of an active metal, e.g., aluminum in the melting salt mixture. The hydrogen chloride or water attacks the metal when the temperature is raised above 500° C. The attack generally continues for several hours and is evidenced by an evolution of gas. When gas is no longer given off, the salt mixture is free of those two impurities.

Preferably, the salt mixture meets the following specifications. It has a melting point from 385° C. to 393° C. It is judged sufficiently dry by test such that an immersion of magnesium metal in a melt of the salt at a temperature in excess of 455° C. results in a gas generation rate not exceeding 1.6 × 10^-5 m³ s^-1 per m² of magnesium surface. Further, the solid mixture dissolves in water producing an insoluble residue not exceding 9% of the mass of the solid placed in the water.

The thermal-energy storage material of this invention may be used in any type of hot-gas engine, such as one using a polyatomic gas in a closed cycle circulation system having a conventional steam turbine. One system is described in Chubb, T.A., "Analysis of Gas Dissociation Solar Thermal Power System", in Solar Energy, 17 (2-D): p. 129-36, 1975; in U.S. Pat. No. 3,972,183 of T.A. Chubb; and in U.S. Pat. No. 3,997,001 of T.A. Chubb. All three above references are incorporated herein by reference. Briefly,, energy is stored and released in the above systems in the following manner. The salt mixture is packaged in an assemblage of small, partially filled metal containers mounted on racks inside an airtight tank. During the daytime, energy is introduced to the tank by "heat release" pipes at the bottom of the tank. This energy is derived from a chemical reaction 1/2 O₂ + SO₂ → SO₃ that occurs as the gas stream from a solar collection field passes over a catalyst bed contained in the pipes. The heat release pipes are embedded in a pool of m-terphenyl liquid. Energy input causes the terphenyl to boil and increases its vapor pressure within the tank resulting in condensation on the outside surfaces of the salt cans. The heat-of-condensation of terphenyl causes the salt within the cans to melt.

During the night when energy is no longer being supplied to the heat-release piping, the pool of liquid at the bottom of the tank cools so that the salt cans become the hottest portion of the tank assembly. The sides of the cans are continuously wetted with liquid terphenyl supplied by a pump and spray system. The surface film evaporates, cooling the salt and maintaining a high vapor pressure of terphenyl within the tank. Energy is withdrawn from the tank by introducing water into steam generator lines at the top. Condensation of terphenyl vapor on the steam lines delivers heat to the steam generator lines, boiling the introduced water and superheating the resultant steam.

Having generally described the invention, the following examples are given for purposes of illustration. It is to be understood that the invention is not limited to these examples, but is susceptible to different modifications that would be recognized by one of ordinary skill in the art.

EXAMPLE I

Chloride salts which meet the preferred specifications were selected. A 200 gm salt mixture comprising 24.5 weight percent of sodium chloride, 20.5 weight percent of potassium chloride, and 55.0 weight percent of magnesium chloride was prepared and was dried of water and hydrogen chloride. Subsequently the mixture was reheated in a thick-walled aluminum crucible. The variation of the temperature with time is shown in FIG. 1. During reheat, plateau "A" results from the melting of the salt mixture. After heat or power is cut off, the mixture cools. Plateau "B" results from freezing of the salt mixture.

EXAMPLE II

A 2262 gm sample of the same mixture and of the same specifications as Example I was prepared by the technique of Example I. The sample was placed in a 1152 gm thick-walled crucible and was heated electrically. The sample was heated with an applied power of 906.7 watts. FIG. 2 shows the variation of the sample temperature with time. The heat of fusion was calculated to be between 97 and 98 cal/gm.

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

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Thermal energy storage material comprising mixtures of sodium, potassium and magnesium chlorides - US Patent 4119556 Description

SATA vs. EIDE hard drive: what's the difference?

You need a SATA controller to attache SATA hard drive. Lots of motherboards come with these on board in addition to the EIDE and cards are available. The technologies don't conflict, but they are definitely not interchangeable. SATA transferring data faster, but is only 7 pin connector. how come can be faster than 80 conductor IDE? (i also understand that USB is faster than parellel port, but still wanna know the technical issue inside.)

http://www.maxtor.com/en/technologies/serial_ata/faq.htm

Be aware with SATA, most of the bios needs upgrade even if they have SATA controller on that. High-end motherboards use the ICH5 Southbridge (part of Intel 875P chipset). ICH5 has 2 SATA ports integrated. Silicon Image is another chip manufacturer used for on-board SATA support.

Right now the speed difference between SATA-150 and ATA-133 or ATA-100 is negligible.  Even 7200rpm drives can't usually sustain more than 50 megabytes/sec of transfer anyway, let alone 100, 133, or 150MB/sec.

Obviously the extra bandwidth comes into play when you've got multiple devices on a single IDE channel but if performance was really that critical you'd have every device on its own connector.

The primary difference is: SATA is the future, PATA is the past.

The SATA connectors are much more convenient, the cost increase now is negligable (and will flip as time goes on), and the ceiling is much, much higher. SATA has none of PATA's limitations.

But should you replace PATA drives today with SATA drives? No. Should you consider using SATA if you get a new PC or motherboard with SATA support, and you have to buy drives anyway?

Oh, plus, if performance is an issue, SATA has 10k drives available (36 and 72GB). PATA does not. An array of 10k SATA drives is damn fast. Server fast.

You can also buy adapters between SATA and EIDE.  I'm not sure all configurations are supported, but you should be able to go between EIDE connectors on the motherboard and a SATA drive.

Regarding performance of SATA drives:

http://research.microsoft.com/~Gray/papers/MSR_TR_2003_70_%20SATAPerformance.pdf

A Quick Look at SATA Disk Performance

We have been investigating the use of low-cost, commodity components for multi-terabyte SQL Server databases. Dubbed Storage Bricks, these servers are white box PCs containing the largest ATA drives, value-priced AMD or Intel processors, and inexpensive ECC memory. One issue has been the wiring mess, air flow problems, length restrictions, and connector failures created by seven or more Parallel ATA (PATA) ribbon cables and drives. Large capacity Serial ATA (SATA) drives have recently become widely available for the PC environment at a reasonable price (1k$/TB). In addition to being faster, the SATA connectors seem more reliable, have a more reasonable length restriction (1m) and allow better airflow. We tested two drive brands along with two RAID controllers to evaluate SATA drive performance and reliability. Each disk delivers about 50 MBps sequential and about 75 read IOps and 130 write IOps on random IO. The cards saturate at 200MBps on sequential but scale linearly to 8 disks for random IO. A surprise is that software RAID1 generally performs best and is easiest to manage."

"You can also buy adapters between SATA and EIDE.  But it is not sure all configurations are supported, but you should be able to go between EIDE connectors on the motherboard and a SATA drive".

I thought they had ones that went both ways, but I could be wrong.  Why would you want it?  So that drive manufacturers have an incentive to start making SATA drives right away without risk of reducing their market from people who still only have PATA connectors.

I've accidentally ruined so many PATA cables (by pulling the socket thing off the ribbon) that I was really looking forward to SATA... But alas, the SATA connector is still a flimsy little plastic thing. It doesn't even lock in place.

I'm not sure what the whole point of ATA is these days; why not just use FireWire? (probably because the controller needed between the bus and the disk is still fairly expensive... but it would be so much nicer to run your whole storage system on one or more hot-plug FireWire buses)

Out of curiosity, if more people used SCSI, would the prices come down to IDE levels? Or do the drive electronics mandate a minimum pricing?

The cost difference between SCSI and IDE drives is not just the interface.  Largely it is the market targeted by the drive makers.  They design their SCSI drives for business use, and therefore make them more reliable and faster.  IDE drives are for consumer use so they are made to be as inexpensive as possible.

It is possible to make SATA drives on par with SCSI drives, for a price.  I imagine it would be possible to make SCSI drives almost as cheap as IDE drives, but it is not worth it since there is not a mass market for SCSI drives, especially now with SATA.

I have heard that the Western Digital Raptors (the 10K SATA drives) actual share drive hardware with their SCSI cousins, which is why they're available in the common SCSI sizes (36GB and 72GB) and not in the more typical PATA sizes.

The biggest question most of we can't answer is the difference between SATA and PATA or as the techno-weenies call it "regular hard drives". Because this forum pretty much saves me about a 15 to 25 minute education process for customers, I would like to thank you guys for having this thread up here for me to print and hand to people and let the PEBKACs slowly do the math themselves.  On a slightly related note tho...I haven't seen much thought being put out on one potential for SATA...I could be wrong but listen for a minute...the S in SATA is Serial..we have had serial ports for awhile and know how they work..USB (still a Serial Bus) made things easier..one of the nice things about USB being on a "serial bus" its biggest point of sale is "hot swapable" And from what I have been reading about all of the PCI-X stuff..being that everything there is going to be a serial bus..the most simple things like sound cards/modems/nics/ EVEN Video cards are gonna be hot swappable.

Granted that its not the primary drive that you have booted from and are now using an operating system on...would your SATA drive currently be hot swapable...or is that something that is currently limited by todays Parrallel interface bus south bridges.  Or am i the first to ask that?    (on a related note i know i have lost any and all ability to spell).

Some people said that PATA is faster than SATA, in some case.

but the technical note, certified that SATA is much more better than PATA. How is the PATA works when transferring data with 80 conductor IDE cable?

Purely from a performance (gaming) point of view, how do the current crop of PATA and SATA drives match up? Also, how much difference does an 8mb cache vs 2mb cache make?

The price diffential between PATA Seagate 120Gb and SATA. Seagate 120GB(2mb, I haven't checked out 8mbs yet) is nearly 15%, 4400 bucks to 5600 bucks. Also whats the advantages and Disadvantages of Maxtor vs. Seagate. I also hear a lot of scare stories of how the PATA 2mb 120gb seagate is crashing a lot. Anyone heard anything?

Gas is stolen in bags