Understanding the difference between AC and DC

Electric current flows in either alternating current (AC) or direct current (DC). Whether AC or DC, both are essential to the proper functioning of our appliances or electronics.

What is Alternating Current (AC)?

The critical difference between alternating current and direct current lies in the direction in which electric charges flow.

Alternating current (AC) power is the standard electricity that comes out of power outlets. In alternating current, electrons continuously change their directions from forward to backward periodically.

AC is used in powerhouses and buildings because generating and transporting AC across long distances is relatively easy. AC is the most commonly used and most-pr  eferred electric power for household equipment, office, buildings, etc., and is capable of powering electric motors which are used in refrigerators, washing machines, etc.

What is Direct Current (DC)?

Direct current (DC) power, as you may suss from the name, is a linear electrical current. Unlike alternating currents, the flow of direct currents does not change periodically. The current electricity flows in a single direction in a steady voltage.

Direct current can come from multiple sources, including batteries, solar cells, fuel cells, and some modified alternators.

Everything that runs on a battery and uses an AC DC adapter while plugging into a wall or that runs on a battery depends on Direct Current.

The major use of DC is to supply power to electrical devices and also to charge batteries. Some examples of DC include flashlights, mobile phone batteries, flat-screen television, and more.
Ac adapter waterproof


Why Do We Need Two Different Power Supply Types?

The smooth flow and uniform voltage of DC power make it more popular for electronic and electrical devices, but we can't survive without AC power.

Almost all power outlets supply buildings with power in the form of AC, due to the fact that DC power cannot travel the same long distances from the power plant to the building as AC power can.

Smartphones, laptops, flashlights, and anything else that is battery-powered rely on storing DC power. Both power types are essential, and one is not better than the other.


How Is AC Power Turned into DC Power?

DC is less popular for long-distance transmission, and in some cases converting AC to DC requires a power supply consisting of a transformer. The conversion of AC to DC helps to prevent the reverse flow of current.



The purpose of distinguishing between DC and AC power is to better arrange what electricity should be used on each occasion, so as to save electricity equipment and electricity costs. Regardless of the type of power supply, electrical safety is something we must pay attention to.

It is worth mentioning that swappable external power supply units provide more flexibility. It will bring a lot of inconvenience to our daily use without a power supply adapter. When purchasing and using an AC/DC adapter or charger, choose one that provides at least the power required by your device. Consulting a professional power adapter manufacturer and power adapter supplier can help you learn more.