Constant voltage power adapter converts the main power AC 100-240V AC into a smaller usually DC voltage that your end device needs to operate. Usually these are required for charging or powering operated devices.
When you purchase, the best way is to check if your device has a specific power adapter already available. If you can not find one then you can find out what your device needs to operate, so inspect the device and look for any labels that indicate either the voltage or mAh/A.
Choosing the right power adaptor specs to make sure you check the following:
Voltage carries the power and the Amps are the measurement of how much power it consumes, the basic equations are here:
W(wattage)=V(voltage) x A(amps)
A(amps)=W(wattage) / V(voltage)
V(voltage)=W(wattage) / A(amps)
Meanwhile, to increase the reliability of the power supplies, we suggest clients choose a unit that has a rating of 30% more power than actual need. For example, if your device needs a 50W power source, we suggest that clients choose a power adapter with 65W of output power or more. In this way you can effectively increase the reliability of the adaptor in your system.