Wednesday, October 31, 2007

Understanding Electric Motors

The world of electric motors is quite fascinating. For many making and collecting various types of electric motors is a hobby and for others making the best electric motors to power various devices is a profession. Whatever the approach is, but electric motors offer innumerable possibilities for improvisation. Working with electric motors and understanding them is a rewarding and learning experience. Let us find out more about electric motors in general. Usually, electric motors can be classified into two main types. They are direct current or DC and alternating current or AC motors. DC or AC is very common terms and they refer to how the electrical current is transferred through and from the motor. Both types of motors have different utilities and uses.

DC motors are usually available in two general types. Alike that, AC motors also come in two different types. They can be two phase or three phase AC motors. Although on technical front, the differences in DC and AC motors are sometimes marginal, but some of these differences make one types better than the other for a certain use. In general, the DC electric motors work for conditions controlling the speed is essential. It is due to the factor that DC motors have a steady and constant current. DC motors are also the first and earliest motors used. But these good factors are also accompanied with some limitations; for instance, the DC electric motors are incapable of producing power over long period of time. Most of the electric companies are aware of the limitation of the DC motor and have found that the power was lost as the electric current was transmitted. One of the variant, the Brush DC motors, use certain rings that conduct the current and form the magnetic drive that runs the rotor. On the other hand, the brush-less DC electric motors bring forth a switch to generate the magnetic drive that powers the rotor. Direct current motors commonly used in most of the electric appliances in your home.

Now coming back to the AC motors we find that these kinds of motors are commonly used on the basis of their type. For instance, the single phase AC motors are used for general purpose. This type of motors will work efficiently in different conditions. AC motors are effective for systems that are hard to start because they need a lot of power for this purpose. The three phase AC motors, also called polyphase, are commonly found in industrial sector. The AC motors have a high starting power built to transmit lower levels of overall power. As it alternated the power, so it gets its name AC. The amount of power specified by an AC motor is determined by the amount of power needed to operate the system.

Generally, the DC and AC electric motors are easily come across everywhere from the home to the car to industrial uses. The introduction of DC motors is still considered no less than a revolution and when AC motors were available in the market the way motors were looked at changed because of their amazing starting power potential. DC motors and AC motors are different in many ways, but they still both are used to power the world of electric appliances.



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Your Guide to Hidden Cameras and Other Security Cameras

With Father's Day just around the corner, it's time once again to figure out what I'm going to get my dad. Like many men, he's an electronics enthusiast through and through. He's what companies like (or love) to call an "early adopter" - someone who just can't wait to buy the latest gadget, the faster computer, the bigger HDTV, and anything else you can think of. His obsession definitely has its benefits, though. My sister and I regularly go through his "electronics graveyard" and get fully functional computers, DVD recorders, and all manner of accessories.

But this knack of his to buy the latest electronics makes it that much more difficult to figure out what to get him for his birthday, Christmas, and Father's Day. My sister and I are thinking about buying him a new digital camera for Father's Day, one that has 7.0 megapixels, an optical zoom, and a special setting for taking eBay pictures. Dad is an avid eBay seller, and the right photos can make the difference between selling an item at a decent price and at a great price. The new digital cameras that have the special eBay setting would complement two of his passions: electronics and eBay.

We're also considering buying him a GPS receiver. The Global Positioning System is a set of satellites in orbit high above the earth, and a GPS receiver can tell you, in terms of latitude and longitude, exactly where you are. Some GPS receivers have built-in mapping tools that not only include road maps, but that also show places of interest. So, for example, when Dad's traveling and needs to find a gas station, he can "ask" the GPS system where the nearest gas station is, and then receive directions to it.

A GPS receiver is also perfect for a new "sport" that I've become interested in, and one that I think Dad would love. Geocaching is a hobby that is quite a bit like a treasure hunt. People all over the globe hide small containers that contain trinkets and logbooks, ascertain the latitudinal and longitudinal coordinates of the hiding spots, and post them online. You can go online and find the coordinates of caches near where you live or travel, enter them into your GPS receiver, and then try and find the cache. It's not as easy as it sounds, but it sure is a lot of fun. Once you find a cache, you can pick up a trinket, leave a trinket, and sign the logbook. Dad's expressed an interest in geocaching, and since he does a lot of traveling for his work, my sister and I think that a GPS receiver and a book on geocaching might make the perfect Father's Day gift.

In my heart, I know that our dad will appreciate whatever gift we choose. Any type of electronics will tickle his fancy, and I'm sure that he'll enjoy either a digital camera or a GPS system. The only thing we have to worry about is whether he'll go out and buy one for himself before we get a chance to give him his Father's Day gift!Hidden cameras have become very popular in recent years with business owners, law enforcement officers and parents. Business owners often use surveillance systems to keep an eye on employees or their store to protect the business from theft or abuse. Hidden cameras are used by the police to catch criminals in the act or to record arrests as they occur. Parents use nanny cams to make sure their children are being properly treated. If you're thinking of buying a hidden camera or other type of security camera, here's a quick guide below.

How Hidden Cameras Work

There are two types of hidden cameras - wireless and wired. Wireless hidden cameras use batteries and have the camera and transmitter concealed with no visible wire from the camera to the recording equipment. Wired cameras will have a physical wire running from a VCR or PC to the camera.

To determine if you need a wireless or wired hidden camera, consider the length of time you will need to record. Will the batteries hold up long enough? The location of the hidden camera is also important. Hidden cameras come in a variety of shapes, forms and themes. Choose a camera that goes well with the environment around so it will be unnoticeable. Some cameras feature wide-angle viewing, which comes in handy when you need to survey a large area. Also, the lighting of the area is important. Check the hidden camera's resolution before buying.

Types of Hidden Cameras and Security Cameras

There are many types of hidden cameras and security cameras for all situations. From dummy cameras to professional cameras, each one serves its own unique purpose. Here are some types of cameras and their benefits.

Nanny Cams

Protect your children throughout the day with a nanny cam. Even if you have a nanny you feel you can trust, it doesn't hurt to have a nanny cam for the safety of your children and home. Nanny cams are actually hidden cameras that come in many shapes and sizes. The camera might be embedded in children's items such as teddy bears, backpacks, baby wipe containers, dolls, stuffed animals, etc. These items can be placed in the child's room along with other toys. There are also nanny cams for other rooms of the home, including clocks, radios, table lamps, food containers, thermostats, pillows, picture frames, hair dryers, DVD players, etc. Every room can have a nanny cam if needed. Check with your local law enforcement before getting a nanny cam or hidden camera for your home to be sure there are no restrictions.

Surveillance Systems

If you need more than a few hidden cameras, consider a surveillance system. Surveillance systems enable you to observe multiple locations through one sophisticated system. With a channel DVR system, hidden cameras are set up in different areas and interconnected so you can survey all the areas through multiple channels. You can expand your surveillance system as your business or operation grows. There are also portable DVR surveillance systems and those that enable you to monitor the area from any location online.

Monitors

Monitors are screens that show what is going on as it happens. Many public places have monitors set up to let people know they are being recorded. Some monitors are used by the owners or security guards to keep an eye on areas from behind the scenes.

Dummy Cameras

Dummy cameras are not hidden cameras or even real security cameras. They look like real security cameras and give an appearance that the area is being recorded. The thieves won't know if the camera is real or not. Dummy cameras are often used as a deterrent by many business owners.

Professional Cameras

Professional cameras are often used to survey large businesses or offices, inside or outside. They can be mounted on walls or ceiling brackets. Some are waterproof for outdoor surveillance. A variety of professional cameras are available for different situations.

Hidden cameras and security cameras are great for protecting your children, home, business or property. Use the guide above to find the hidden camera or security camera that's right for you.



http://www.articlefair.com/Article/Your-Guide-to-Hidden-Cameras-and-Other-Security-Cameras/15678