The AC adapter, AC/DC adapter or AC/DC converter is a type of external power supply, often enclosed in what looks like an over-sized AC plug. Other names include plug pack, plug-in adapter, adapter block, domestic mains adapter, line power adapter, or power adapter. Informal terms include wall wart, wall cube and power brick. AC adapters are typically used with electrical devices that do not contain their own internal power supply. The internal circuitry of an external power supply is very similar to the design that would be used for a built-in or internal supply, but there are several advantages of separating the power supply from the main body of the electronic device, as explained below.
WiresThe AC Adapters wiring differs slightly from ordinary standard wiring. For connecting regular wires we know that black goes to black, and red goes to red, right? Well...not in the case of an AC Adapter. Look closely at the wires, one should have writing, or a white stripe on it. That's the positive wire and it connects to the positive side of the battery. The other plain black wire will go to ground.