Generators | Three Phase vs Single Phase Power

October 07, 2020 Aurora Generators Inc.
Generators | Three Phase vs Single Phase Power
Show Notes Transcript

What is the difference between single and three-phase power?  What type of generator do you need?  How do they work and why choose one over the other. 

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There Are Two Types Of Systems Available In Electric Circuit:

First, let us start by saying, most homes in North America use single-phase power.    Three-phase power is primarily for industrial use.

So, let me explain what the difference is.

Single-phase and three-phase generators provide power differently. The most obvious evidence of this is seen in power delivery. Both types provide AC power, but a three-phase system produces three separate waves of power, delivered in sequence. This ensures a continuous, uninterrupted energy flow that never drops to zero and makes three-phase generators more powerful than single-phase generators.

Single-phase generators deliver one constant wave of power; however, the power level varies with the electrical current coming in. That means power levels can drop to zero during the cycle. This happens very quickly and is undetected by humans and rarely affects whatever device is being powered.

In fact, residential power is single-phase, and there’s never a problem powering devices in our homes. But for very large and demanding power applications, this dip can cause harm, which is why three-phase systems exist.

The easiest way to visualize these power differences is to imagine a wave.  One single wave (i.e., a single-phase system) starts at zero, goes up to the peak, and goes back down to zero before the next wave starts.

In a three-wave system, the three waves in sequence each individually look and act the same as the single wave. But, since they arrive in sequence, their total power overlaps a bit.

Three-phase provides more power than the single-phase circuit, keeping that power always above zero. 

Power is distributed over the entire load over three phases/waves, so there is less draw on one single wave.

So,  If you’re questioning whether you need a single-phase or a three-phase generator, you need to think about your power needs and budget.

Single-phase systems are less complex and less costly. They are more common in residential or rural applications where the loads are relatively small.

Unsurprisingly, 3-phase systems are more costly to install and maintain, but they may be a necessity depending on your power needs.

3-phase systems are ideal for high-capacity settings, which is why you usually only see them in industrial and commercial areas. Data centers, in particular, benefit from 3-phase backup generators due to the increased distribution capacity. 3-phase systems can power multiple racks, whereas single-phase systems cannot.