Generators are designed to produce power during an outage or when access to the main supply is unfeasible. The two main types of generators used in these settings are an AC generator and a DC generator. While both units can effectively provide energy, the two systems follow slightly different practices and culminate a somewhat different outcome.

What are AC and DC Generators?

An AC generator converts mechanical energy into electrical energy in the form of alternative EMF or alternating current. This system follows the Electromagnetic Induction theory, which suggests that electromotive force (EMF or Voltage) is generated in a conductor that cuts through a uniform magnetic field. This process can be achieved by rotating a conducting coil in a static magnetic field, or by turning the magnetic field that contains the stationary conductor.

A DC generator transforms mechanical energy into DC – Direct Current electricity. This energy alteration process employs the theory of Induced Electromotive Force. When a conductor is placed in the varying field, an EMF is induced within the conductor. The circulation of induced current takes place within a closed path, and the induced current direction is stable.

What is the difference between an AC and a DC generator?

Current Direction

The main difference between an AC and DC generator is that in an AC unit, the electrical current reverses direction occasionally. This alternating current direction is caused by the south and north poles of the magnetic, which force the flow into opposite directions. A DC generator has a fixed coil that rotates in a fixed field, meaning the electrical current flows progressively in one direction. The two ends of the coil are attached to the commutator, which balances the chargers and ensures the current does not alternate direction.

Output Voltage

An AC generator produces an output voltage that varies in time and amplitude. In comparison, a DC generator generates a steady output power that does not differ in time and amplitude. This stable current is a result of the commutator which balances the voltage.


AC and DC generators have varying safety hazards. The output capacity of an AC generator is typically more than 120 volts. This high voltage can sometimes cause severe injury or even death if it comes into contact with the human body. A DC generator is generally much lower in voltage and is much less likely to cause any severe damage to humans. For a DC flow to produce the same effect on a person as AC, the constant strength must be at least two to four times greater.


DC generators usually provide seamless connectivity and efficient flow of power. This simple connectivity is the result of operating without a transfer switch. An AC generator is typically much more advanced and requires considerable expertise and engineering to transfer electricity to remote sections of the grid. This more complex process also generally incurs much higher expenses.

What are the different applications of AC and DC generators?

AC generators are a common option to service home electrical appliances and small motors, including juicers, vacuum cleaners and food mixers. DC generators have much more significant application potential. These uses include big electrical motors and complex electrical systems. The efficient and reliable supply of energy from a DC generator effectively charges batteries for off-grid.

What are the advantages of AC and DC Generators?

AC Generator Advantages

– The absences of brushes ensures minimal maintenance time is required
– AC generators are typically more compact and smaller in size
– The unit generally has a minimal amount of losses
– The breakers used are relatively smaller when compared to DC generators

DC Generator Advantages

– Cables costs are generally much less as there is no shielding from radiation
– The constant coil arrangement reduces fluctuations in the generator
– Operating characteristics depend on the field winding

Reactive Generators

Reactive Generators are a proven and trustworthy generator service provider for Queensland residents. We work with each client to establish their individual needs, goals and budget, before recommending the perfect generator for their circumstances. After guiding our clients through the purchase process, we also provide a comprehensive range of generator servicing and maintenance options. These one-off or ongoing maintenance regimes ensure you will get the most out of your purchase and capitalise on the device’s expected lifespan. We always keep a diverse range of premium spare parts and replacements on-site at all times, to ensure that we can provide timely and long-lasting solutions. Working across Queensland, you can find Reactive Generators teams in Brisbane, Ipswich, Gold Coast and Sunshine Coast. If you’re still unsure whether you require an AC or DC unit, get in touch with the friendly team at Reactive Generators for further information.