Alternating Current (AC) vs Direct Current (DC), the guide for you
Ever wondered what are the currents that are running through your wires? This guide will walk you through the 2 types of currents; Alternative Current (AC), Direct Current (DC) and what it all means.
In this guide, I’ll be covering the essentials ranging from:
- What are AC and DC
- Differences between AC and DC
- Converting AC to DC
- Whether to use AC or DC
- Applications of AC and DC
- Coupling with AC and DC
AC vs DC
Alternating Current (AC)
- A form of current that changes direction periodically, oscillating back and forth
Direct Current (DC)
- A form of current that only flows in one direction, providing a constant voltage/current
What are the differences?
AC | DC | |
---|---|---|
Waveform produced |
Most commonly produces sine wave | Constant voltage/current tend to produce horizontal waveforms |
Generated by | Alternator, an electrical generator designed to produce AC | Commutator Rectifier, converts AC to DC Batteries, through generation from a internal chemical reaction |
Suitability for long-distance transmission | Suitable, transmission loss is small | Less suitable, transmission loss is bigger unless it’s high enough in voltage |
Usages | Less suitable for electronic products unless power is switched into DC through rectifier | Suitable for electronic products |
Safety Level | Lower safety level Alternating voltages can cause current to enter human body without closed loop |
Higher safety level Commonly found DC currents in electical appliances tend to be safer |
Converting AC to DC?
Although AC and DC operate differently, they need not be operating as a standalone circuit due to the availability of an AC-DC converter.
The converter is called a rectifier, where it transforms AC input into DC output through reversing the directional flow of current.
AC vs DC, which should you use?
Long Distance Power Transmission:
- AC: The ability to ramp up voltages through transformers results in lesser resistance in the wires which can provide efficient transmission of long-distance power
- DC: High difficulty and cost to efficiently create high voltage DC
Winner: AC, the one that does the job if you’re looking to transmit power over a long distance
Ease of Usage/Simplicity:
- AC: Simple to operate through the usage of wires and transformers for voltage adjustments
- DC: Unable to conveniently convert voltages due to requiring complicated circuits
Winner: AC, the convenience and flexibility that it’s able to bring unravels its opposition.
Compatibility with electronics:
- AC: Less compatible with electronics due to the directional changes of current
- DC: More compatible with electronics as current flows reliably in one direction
Winner: DC, the solution to power your electronics.
Applications of AC and DC
AC

Delivers power to:
Houses, Offices, Electric Motors, Generators
DC

Delivers power to:
Electrical Appliances; Cell Phones, TV, electric vehicles, etc.
Lauren. (2017, July 17). AC and DC electricity made simple.
Coupling: AC and DC
AC and DC can also be referred to as the Alternating (Capacitive) Coupling and Direct Coupling. Coupling allows you to observe the voltages and wavelengths of the power supply. Each form of coupling will result in differing results in data when plugged into an oscilloscope.
AC Coupling vs DC Coupling
AC Coupling | DC Coupling |
---|---|
Only show and allow AC signals to pass through a connection | Allows for both AC and DC signals to pass through a connection |
Suitable for the following sensors: ICP Microphones ICP Accelerometors Strain Gauges (Elastic or Dynamic behaviour only) ALL ICP/IEPE transducers |
Suitable for the following sensors: Thermocouples DC Accelerometer Strain Gauges |
Start coupling with:
DSO Nano V3: A portable DC coupling capable oscilloscope for voltage measurements

The DSO Nano V3 is a simple to use and compact oscilloscope that meets the basic demands of users ranging from school lab tests, electric engineering, etc.
Product Features:
- Portable and lightweight
- Color display
- Waveform storage and playback
- 6 triggering modes
- 200Khz Analog Bandwidth
- Complete measurement markers and signal characteristics
- Built-in Signal Generator
- Accessories available
- Open Source
Summary
Choosing between using DC and AC comes down to the purpose and requirements of your project. DC is recommended for powering electronic devices due to the nature of batteries being powered by DC current. On the other hand, the ease of where AC voltages can be modulated is still unmatched. With that said, both currents are indeed excellent in their field of area and it solely comes down to the user application in picking the right one.