Laptop batteries require direct current (DC) in specific measurements.In laptop adapter shop,Your household electrical outlets supply approximately 120 volts of alternating current (AC), which would severely damage your battery if plugged in directly. Laptop adapters convert that 120 volts of AC to a much smaller concentration of DC. Exact power requirements vary according to the battery you are charging, and even among laptops from the same maker, the voltage can vary significantly. The best source for a compatible AC adapter is your laptop's manufacturer, but a few "universal" adapters will work with most laptops.
1.Power down your laptop, and turn it over.
2.Locate the battery compartment on the underside,Samsung PA-1400-14 and write down the power settings, which are noted in watts or volts of direct current and amps. Laptop wattages vary but are commonly between 65 and 120. On some laptops, you may find an information sticker that says "19V DC -- 3.8A," which means it requires 19 volts of direct current with a 3.8 amp rating. If your computer notes volts and amps but not watts, multiply the volts by the amps to get the approximate wattage, which in the case above is 72.
3.Locate the computer's make and model number,HP F1454A AC adapter which are also likely to be on the underside of your computer.
4.Visit an electronics retailer, either in person or online,Toshiba PA3715U-1ACA and type your computer's make and model into the search box, or give these details to the clerk on duty, and ask for a compatible adapter.
5.Navigate through the Compaq Presario CQ50 site's controls to find adapters for your laptop model if you are searching online. They may be under "Accessories."
6.Locate the voltage and amperage on the charger recommended by the clerk or website. If you are searching online, this may be under "Specifications." Make sure the numbers are approximately equal to your battery's requirements.HP 394224-001 A small amount lower will not hurt your laptop, but too much power will.
7.Check the jack on the charger that will connect to the computer to make sure it is physically compatible with your laptop's DC input jack. Universal chargers may come with several adapter heads. If you are shopping online,Compaq Presario CQ56 the technical specifications will list the compatible laptop models.
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