How2Day: AC Adapter Plug Types

There are three different types of AC adapter plugs. Jupiterimages/Photos.com/Getty Images
AC adapter plugs, or AC-to-DC adapters, are electrical plugs designed to change high line voltage, or alternating current, into low voltage, or direct current. Small electronic devices like gaming systems, cordless telephones and laptop computers use AC adapters. AC adapters may also be referred to as external power supplies. Different electronic devices may require a different AC adapter plug to work properly.

Single voltage AC adapter plugs provide power at a fixed voltage. A single voltage adapter provides only one level of DC output. You can purchase single voltage AC adapters in a selection of voltages. You can only use this type of plug on devices that match the voltage or use a lesser current than the plug offers.

Multi-voltage AC adapter plugs are designed with a selector switch, allowing you to change the output of voltage. As long as the tip size and tip polarity of the plug match the intended electronic device, you can use a multi-voltage adapter on a variety of devices. Like the single voltage adapter, you cannot use a multi-voltage AC adapter plug on a device that requires a higher output of current.

This single-voltage adapter plug is primarily designed for use in vehicles. The 12-volt power supply AC adapter plug converts the 12-volt power from vehicles into AC power suitable for smaller electronic devices. These adapters usually have a connecting device that plugs into the vehicle's cigarette lighter, though many newer vehicles now offer additional plugs for such adapters.

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