There are several items that need to be noted on the label of the power adapter.
First, is the model of the power adapter, for example, the model of the power adapter is XVE-120100, it tells us several information, is its manufacturer, wattage, XVE beginning is generally ## company code, 120100 is that the power adapter is 12W, 050200 is 10W.
Second, the INPUT(input) of the power adapter is generally 100-240V~50-60Hz in China, which indicates that the power adapter can work normally under the voltage of 100V-240V.
Third, is the OUTPUT of the power adapter (output), two numbers can be very fast to calculate the wattage of the adapter, such as the power adapter, voltage 12V* current 1A=12W(power), indicating that the power supply is the power adapter of 12W.
Most laptop power adapters are suitable for 100 to 240V AC (50/60Hz). Basically, most laptops have the power supply external, connected to the main computer through a power cord, which can reduce the size and weight of the main computer, only a few models have the power supply built into the main computer.
There is a nameplate on the power adapter, which marks the power, input and output voltage and electricity flow indicators, especially pay attention to the range of input voltage, this is the so-called "travel power adapter", if to the mains voltage only 110V country, this feature is very useful, some parallel laptop is only sold in the origin, There is no such compatible voltage design, even only 110V single input voltage, 220V mains voltage in our country will burn down when it is plugged in.