Your OEM Power Source http://www.currentsolutions.com 2009 Current Solutions, Inc Country Pri. Volt Sec. Volt Freq. Plug 1 Plug 2 Plug 3 Plug 4 Plug 5 Afghanistan 220   50 G         Algeria 127 220 50 G B       Am. Samoa 120 240 60 C A K     Angola 220   50 B         Anguilla (UK) 240   50 D         Antigua 230   60 D K       Argentina 220   50 C B       Aruba 115 127 60 A B G K   Australia 240   50 C         Austria 230   50 A B       Azores 220   50 G B       Bahamas 120   60 K         Bahrain 220   50 D G       Bangladesh 220   50 G B       Barbados 115   50 K         Belgium 230   50 B F       Belize (Br. Hond) 110   60 K         Benin 220   50 C         Bermuda 120   60 D C K     Bolivia 115 220 50 A B K     Bosnia-Herz 220   50 A B       Botswana 220   50 D G       Brazil 110 220 60 B K       Bulgaria 220   50 A B       Burkina Faso 220   50 B         Burma (Myanmar) 230   50 D G       Burundi 220   50 A B F     Cambodia 120 220 50 B         Cameroon 220 230 50 B F       Canada 120   60 K         Canary Is. (Spain) 220   50 B F       Cape Verde, Rep. Of 220   50 A B       Cayman Islands 120   60 K         Central African Rep. 220   60 B         Chad 220   50 A F G     Channel Islands 240   50 D B       Chile 220   50 B I       China, People's Rep. of 220   50 C B       Christmas Is. (Australia) 240   50 C         Cocos Is. (Australia) 240   50 C         Columbia 110 220 60 B         Congo, Rep. of 220   50 B         Cook Is. (N.Z.) 240   50 C         Costa Rica 120   60 K         Curacao Is. 110 220 60 A K       Cyprus 240   50 D         Czechoslovakia 220   50 A B       Denmark 230   50 E B       Djibouti, Rep. of 220   50 F B       Dominica 230   50 D         Ecuador 120   60 K B       Egypt 220   50 B         El Salvador 115   60 K         England 240   50 D G       Equatorial Guinea 220   50 B         Estonia 220   50 A B       Ethiopia 220   50 I A B F G Fili 240   50 C         Finland 230   50 A B       France 230   50 F B       French Guiana 220   50 B F       Gabon 220   50 B F       Gambia 220   50 D         Germany 230   50 A B       Ghana 220   50 D B G     Gilbraltar 230   50 B A       Greece 230   50 B A       Greenland (Den) 220   50 E B       Grenada 230   50 D B G     Guadeloupe 220   50 G F       Guam 110 220 60 K         Guatemala 120   60 K         Guinea 220   50 B F       Guinea-Bissau 220   50 A B       Guyana 110   50/60 D B G K   Country Pri. Volt Sec. Volt Freq. Plug 1 Plug 2 Plug 3 Plug 4 Plug 5 Haiti 110 220 50/60 K         Honduras 110   60 K         Hong Kong 200   50 D G       Hungary 220   50 A         Iceland 220   50 A B       India 220 250 50 G B       Indonesia 220   50 A B       Iran 220   50 A B       Iraq 220   50 D B G     Ireland, Rep. of South 220   50 D A       Isle of Man 240   50 D B       Israel 230   50 H A       Italy 230   50 I B       Ivory Coast 220   50 B         Jamaica 110   50   K         Japan 100   50/60 J         Jordan 220   50 D A B     Kenya 240   50 D G       Korea, South 220   60 K A       Kuwait 240   50 D B G     Laos 220   50 K B       Latvia 220   50 A B       Lebanon 110 220 50 B         Liechtenstein 220   50 L         Lesotho 240   50 G B       Liberia 120   60 D         Libya 127 230 50 I G       Lithuania 220   50 A B       Luxembourg 230   50 A B       Macao 220   50 G B       Madagascar 220   50 B F       Madeira (Portugal) 220   50 G B       Majorca 220   50 A B       Malawi 230   50 D         Malaysia 240   50 D         Maldives 230   50 G         Mali, Rep. of 220   50 B F       Malta 240   50 D         Martinique 220   50 B F       Mauritania 220   50 B         Mauritius 230   50 D B G     Mexico 127   60 K         Monaco 220   50 B F       Mongolia 220   50 B         Montserrat 230   60 D K       Morocco 220   50 A B F G   Mozambique 220   50 A B       Namibia, (W.S. Africa) 220 250 50 G         Nepal 220   50 G         Neth. Antilles 120/127 220 50/60 B A K     Netherlands 230   50 A B       New Caledonia 220   50 B F       New Zealand 230   50 C         Nicaragua 120   60 K         Niger 220   50 B         Nigeria 230   50 D G       North Ireland 220   50 D         No. Mariana Is. (US) 115   60 K         Norfolk Is. 240   50 C         Norway 230   50 A B       Country Pri. Volt Sec. Volt Freq. Plug 1 Plug 2 Plug 3 Plug 4 Plug 5 Okinawa 100 120 60           Oman 240   50 D G       Pakistan 230   50 G B       Panama 110 120 60 K         Papua New Guinea 240   50 C         Paraguay 220   50 B         Peru 110 220 50/60 K         Philippines 115   60 K B       PitcaiM Is. (UK) 240   50 G         Poland 220   50 A B       Portugal 230   50 A B G     Puerto Rico 120   60 K         Qatar 240   50 D G       Romania 220   50 A B       Russia 220   50 A B       Rwanda 220   50 B         Saudi Arabia 127 220 50/60 K A F     Scotland 220   50 D         Senegal 220   50 F         Seychelles 240   50 D G       Sierra Leone 230   50 D G       Singapore 230   50 B D G     Somalia 110 220 50 B F       South Africa 220 250 50 G O       Spain 230   50 B F       Sri Lanka 230   50 G         St. Kitts & Nevis 230   50 D G       St. Lucia 240   50 D         St. Pierre & Miquelon (FR) 115   60 K         St. Vincent 230   50 D         Sudan 240   50 D A B     Surinam 115/font>   60 A B       Svalbard (Norway) 220   50 A B       Swaziland 230   50 G         Sweden 230   50 A B       Switzerland 230   50 B L       Syria 220   50 B         Tahiti 220   50 F         Taiwan 110   60 K         Tanzania 230   50 D G       Thailand 220   50 B K       Togo 220   50 B F       Trinidad & Tobago 115 230 60 D G K     Tunisia 220   50 B         Turkey 220   50 A B       USSR 220   50 A B       Uganda 240   50 G         United Arab Emirates 220   50 D G       United Kingdom & Ireland 240   50 D G       United States 120   60 K         Uruguay 220   50 C B       Venezuela 120   60 K         Vietnam 120 220 50 B F K     Virgin Islands 120   60 K         Wales 220   50 D         Western Samoa 230   50           http://www.currentsolutions.com/articles.php?id=8 Tue, 23 Feb 2010 13:13:04 CST Andrew Robbins Marketing Representative Product Safety Engineering, Inc. Federal Communications CommissionEffective September 9th, 2002, the FCC adopted new conducted emissions requirements, which are harmonized with European standards, based on well-known CISPR limits. These new requirements became "available" for use as of September 9th, 2002 (not mandatory at this time). All products still being manufactured after July 11th, 2005, MUST demonstrate compliance with the new requirement. This rule change basically allows for a sort of transition period where the responsible party may choose to utilize either test limit. As a test lab, it will be PSE's position to test domestic products to the new requirements. If a product fails to conform with the new requirements and would pass the old limits, the responsible party would be offered the choice of using the old requirements knowing the product would need to be re-tested after July 11th, 2005 if the product is still being manufactured. Companies who have already tested a product to the old FCC rules should be aware that a re-test may be necessary if the product is still being manufactured after July 11th, 2005. It is also worth noting that the new FCC rules continue to require conducted emissions measurements to be made with the device powered at 110VAC/60Hz, no the European standard 220VAC/50Hz. http://www.currentsolutions.com/articles.php?id=6 Tue, 23 Feb 2010 13:06:41 CST Melody Williams Business Unit Manager NMB Technologies Corp. Chatsworth, California As consumers demand smaller, faster computer systems, OEM design engineers race to create systems with compact, more powerful microprocessors and chipsets. However these compressed designs provide engineers with a new enemy - heat. In minutes, densely packaged microprocessors or compact electronic systems can generate enough heat to destroy a year's worth of work. A design engineer needs a reliable fan that will maintain system cooling and protect against system meltdown. Most engineers believe that a quality axial fan is the answer to this threat. Yet, many engineers debate over which bearing to use in the axial fan. Since bearing type is a crucial factor in determining an axial fan's reliability, it is important that the design engineer choose the night bearing for the right application. The Criteria There are two main types of bearings that are used in axial fans: ball bearings and sleeve bearings. When choosing between a ball-bearing and a sleeve-bearing fan, the engineer must consider: Fan Longevity Mounting Noise Parts Lubrication Issues Line versus Point Contact Cost (Note: see "At-a-Glance Comparison") Fan Longevity Since fan reliability is the most critical factor in fan performance, it is important that a fan perform consistently for a number of years. The chart below uses the L10 method to illustrate fan performance at various temperatures. LIO refers to the point of time at which 90 percent of a large population of these fan types will continue to work. On average, a fan that operates for 50,000 hours will run continuously for over five years. The chart indicates that when temperatures ranged from 25 to 60 degrees C, ball-bearing fans on average outlasted sleeve-bearing fans by 50 percent. When temperatures exceeded 700 degrees C, ball-bearing fans ran for 45,000 hours, while sleeve-bearing fans became inoperable. Yet, when the ambient temperatures were relatively low, sleeve-bearing fans lasted as long as ball-bearing fans. Therefore, if an application generates high levels of heat, an engineer may want to use a ball-bearing fan. If the equipment generates low-heat intensities, or if the equipment has a short life span, the design engineer may want to use a sleeve-bearing fan. Fan Mounting Another factor that can impact fan longevity is fan mounting. Fans can be positioned horizontally, shaft-centerline parallel or perpendicular to the ground. Fan orientation does not affect the longevity of ball-bearing fans. Ball-bearing fans can be mounted in any position because preloading of the bearings is built-in during the bearing manufacturing stage. Preloading describes the procedure by which manufacturers build an initial side load, such as a spring or a wave washer against the balls, into the ball bearing. This makes the bearing more durable. At-a-Glance Comparison Criteria Ball Bearing Sleeve Bearing Fan Longevity Longer life Shorter life Heat Endurance Higher Lower Fan Mounting Options Vertical, Shaft Center Line Parallel, Perpendicular Vertical Noise Emission Quieter at High Speeds Quieter at Low Speeds in Early Life Parts Precision Non-precision Lubricant Less Evaporation More Evaporation Contact Point Line Cost More Expensive Per Unit Less Expensive Per Unit In comparison, sleeve-bearing fans can maintain life spans comparable to their ball-bearing counterparts when the sleeve-bearing fans are mounted in vertical positions. However, when sleeve-bearing fans are mounted in any position other than vertical, the fan's life span decreases. When selecting a bearing type, the design engineer must consider the orientation for which the fan will be mounted. If the fan needs to be mounted vertically, the engineer might choose a sleeve-bearing fan. However, if the fan is mounted in any orientation other than vertical, the engineer may want to select a ball-bearing fan. Noise In many office environments, noise is a primary consideration for selecting office equipment. The faster a fan runs, the more noise it will generate. While Americans have become acclimated to the hum of the HVAC and computer equipment, many European offices have not. Therefore, many European offices need office equipment that produces minimal noise. In the past, design engineers assumed that sleeve-bearing fans ran more quietly than ball-bearing fans. This is true for applications that have very low fan speeds. Yet, with innovations in preloading, ball-bearing fans can work as quietly as sleeve-bearing fans, especially in applications that require faster fan velocities. With their machine-controlled parts, preloaded ball-bearing fans have exact tolerances that can minimize fan noise. For sleeve-bearing fans, fan noise depends on the clearance of the fan's bushing. The levels of the noise generated will vary with the variance in the component parts. Parts The manufacturing process for ball bearings and sleeve bearings is fundamentally different, resulting in a significant difference in the part precision level. Typically, sleeve bearings deteriorate under high temperatures because they are made from porous, powered metals from a sintering process. Also, sleeve-bearing fans can develop a high micro-hardness that makes secondary machining difficult. Steel parts make ball-bearing fans more exact. They are precision-ground and super-finished. If an engineer is seeking precision parts, ball bearings are the right choice. If an engineer does not need precision parts, sleeve bearings are an alternative. Temperature Ball-Bearing Fan Sleeve-Bearing Fan % Difference 25°C 95K Hours 80K Hours 18% 40°C 75K Hours 52K Hours 44% 50°C 63K Hours 40K Hours 58% 60°C 54K Hours 30K Hours 80% 70°C 45K Hours N/A ---- Lubrication Issues In a computer system, bearing-lubrication failure will cause axial fan failure. Axial fan failure can lead to system failure. To reduce friction and minimize overheating, axial fans need lubrication. Lubricants need to withstand the weight of fan assembly, thrust and rotor assembly imbalance. If the lubricant evaporates, the system can be destroyed. Sealed-for-life ball-bearing systems use thicker lubricants that have more additives, and are less subject to evaporation. While the lubricants within sleeve-bearing fans have a greater concentration of oil, the sleeve-bearings' bushings can only hold a fixed amount of lubricant. Since there is no periodic recharging of the oil, the lubrication within a sleeve-bearing system is more likely to evaporate. Point of Contact As stated earlier, friction will cause failure in axial fans. In addition to the amount of lubricant, the point of contact also dictates the amount of friction an axial fan sustains. The more friction a bearing sustains, the greater the likelihood for axial fan failure. Sleeve bearings are line-contact bearings; therefore, there is broad contact between the shaft and bearing during the back-and-forth sliding motion. This system generates a good deal of friction. Ball bearings are point-contact bearings, which generate minimal friction. Previously, opponents of ball-bearing fans argued that the ball-bearing system could lead to brinelling or indentations in the raceway. Yet, defenders of the ball-bearing system believe that if a ball-bearing system is assembled correctly, each component will fit perfectly, eliminating the potential for parts damage. Cost Considerations When purchased in large quantities, per-unit-sleeve bearings are less expensive. Yet, ball bearings have greater life spans and, over time, provide greater value per dollar. Summary In conclusion, if an engineer is designing a computer system that has a short life span, or a system that will not generate high levels of heat, the engineer may want to select a sleeve-bearing fan. However, if the application is a fast, densely packed microprocessor or a compact electronic system, the engineer may want to choose a ball-bearing fan that will endure hotter temperatures, have a greater life span and ultimately provide a greater long-term investment. http://www.currentsolutions.com/articles.php?id=3 Fri, 24 Apr 2009 12:06:33 CDT The ATX specification is a public specification intended for widespread use in many types of system, and it has been written as a specification for the PC industry, designed to add value to the PC. ATX was developed as an evolution of the Baby-AT form-factor and was defined to address four major areas of improvement: enhanced ease-of-use, better support for current and future I/O, better support for current and future processor technology, and reduced total system cost. By using a power supply that is specially optimized for ATX, it is possible to reduce cooling costs and lower acoustical noise. An ATX power supply, which has a side venting, allows direct cooling of the processor and add-in cards, making a secondary fan or active heatsink unnecessary in most system applications. Download the PDF file from Intel at: http://developer.intel.com/design/motherbd/atx.htm Dowload the PDF file from Teleport at: http://www.teleport.com/~atx/spec/index.htm http://www.currentsolutions.com/articles.php?id=2 Fri, 24 Apr 2009 11:54:04 CDT Lets start with a reality check: Price Target: Often the market you are in will dictate the price point, for example: If you are building a product for the PC or PC peripheral market, you are going to need an inexpensive power supply in order to compete. If you are building a product for the server market, you will need a reliable power supply in order to provide high "availability". Redundancy should be considered also. Production Target: Often the power supply has to be the last thing to be specified. If all the other factors are accounted for, the power supply could be one factor that determines when you go to market. See "Custom or Standard". Now lets begin: Start with your mechanical considerations. Is space a premium? It is best to start with the most space you could possibly allow, then when you find a "safe" supply that could fit the package continue to look for smaller package options. Usually the smaller the package the more advanced it has to be and the more expensive it will be. Do you have any unusual mounting considerations? Will the power supply need to sustain high shock of vibration? Thermal considerations: What is the thermal environment of the power supply? Ambient temperature & temperature rise within the product. What options do you have to keep the power supply running within its intended operating range. No airflow, convection airflow, forced airflow. Conduction? Electrical: DC input or AC Input. What is the desired range of the input? If it is Switching AC input model, the approval agencies may eventually require you to have harmonic correction. If a linear power supply will fit the specifications you desire, you will not be able to use the same model for worldwide input. How many output voltages are required? How tightly do they have to be regulated? What is the duty cycle of each output and how do they relate to each other? What is the output peak requirement for each output and for what duration? Logic & Controls: What signals do you require from the power supply such as "power good/fail"? What signals do you want to send to the power supply such as "Remote Enable" or "Margin"? Do you need a voltage adjustment pot or remote sense on one or more outputs? Do you need "Standby Voltage" to keep a processor idle until called upon to "wake up" by the operator? Approval Agencies: If your product is to eventually be sold in Europe, you will want to consider the CE mark. If it is only going to remain in the United States, you can probably do with the appropriate UL mark. Custom or Standard - General guideline: Here are a few examples that may warrant a custom power supply. You require an extremely cost effective solution for a high volume application, or you require a power supply with features that are not readily available "off the shelf". Impact: A custom power supply will take 12-18 weeks from concept to delivery of "beta" units. Custom units will require engineering fees for design and agency approvals. Custom units do not have the luxury of a proven track record, this makes choosing a manufacturer even more important. Be prepared to work very closely with the manufacturer. Alternative to custom: Value Added Reseller (VAR) A power supply VAR may be an alternate solution that is best for your application. VAR's can configure an off the shelf power supply to meet your requirements. Both electrical and mechanical portions of the power supply are enhanced to meet your needs while retaining the integrity of a proven supply. Smaller engineering fees are required, and some designs are ready in 4 weeks. 2nd Alternative to custom: Modified standard Modified standards are a good alternative when you find a power supply that has a most of the requirements you desire, but lacks in one portion of the spec. Less than half of the powers supply manufacturers are good choices to consider for modified standard. It requires a strong engineering staff and a strong knowledge of the power supply circuit characteristics. The beauty of modified standards is that they can give you a custom fit for a standard price. In many cases there is minimal or no agency costs. Additionally, some manufacturers will amortize the cost over a blanket order. http://www.currentsolutions.com/articles.php?id=1 Fri, 24 Apr 2009 11:52:16 CDT