Single-Phase vs 3-Phase Power Protection: What You Need to Know

September 17, 2021 by CyberPower

Single-Phase vs 3-Phase Power Protection: What You Need to Know
Power is power, right? Well not exactly. It’s true that most of the electrical power we use is alternating current (AC) power generated by utility companies. In fact, AC power is used to deliver the vast majority of the power to our homes and businesses. But AC power can be delivered in many ways, the two most common being single-phase and 3-phase. For businesses, it’s important to understand which type of electrical power is right for your application and protecting that power with a compatible Uninterruptible Power Supply (UPS) system.

What is Single-Phase Power?
Single-phase power is the most common form of AC power delivery. Because residential power requirements are generally much less than business power requirements, single-phase is sufficient.

The term Alternating Current, or AC, describes how the power alternates in cycles as the voltage peaks and dips continuously between a positive and negative amplitude. As you might expect, single-phase power produces a single wave of power, as shown below:

This graph shows that the power output of a single-phase power supply is not constant, meaning its voltage rises and falls as it passes through zero twice per cycle. During these moments, there is a temporary absence of power. So, single-phase power is not constant. While satisfactory for most residential needs, a standard 15A, 120V branch circuit can only support electrical loads up to 1800 watts. A home with a 100A, 240V electrical utility supply is limited to loads up to 24,000V.

What is 3-Phase Power?
Unlike single-phase, 3-phase power produces three separate wave currents so there is no temporary absence of power.

3-Phase power delivers power at a steady, constant rate and can reach higher voltage levels up to 480V in the USA. This steady stream of power and ability to handle higher loads makes a 3-phase supply ideal for industrial and commercial operations.

To learn more about different types of power, click here

More Waves. Less Cost.
A 3-phase circuit provides greater power density than a single-phase circuit so it can deliver the same amperage with smaller size wires making 3-phase more efficient. In fact, compared to single-phase power circuits, 3-phase power circuits provide almost twice the power with the same current while only requiring one additional wire.

Using 3-phase power can save on electrical costs by reducing the current requirements and wire size. Utilizing more power in less space lowers cabling and operating costs, delays capital expenditures and ensures scalability for future infrastructure growth.

With its cost savings and flexibility, it’s easy to see why 3-phase is popular in power hungry high-density IT installations and data centers. Other industrial businesses such as warehouses, fabrication, and manufacturing also benefit from the efficiency offered by 3-phase power.

Which Type of Power is Best for Your Business?
First, find out what you have now. The easiest way is by looking at your Electricity Supply Meter. Single-phase power may be listed as single, mono-phase or 1-phase. 3-Phase power may also be noted a tri-phase or polyphase.

Image: 3-Phase Circuit Breaker
You can also check the width of the master switch on your power panel. Single-phase power features a Master Switch that is only two poles wide. 3-Phase power features a Master Switch that is three poles wide.

Image: Single-Phase Circuit Breaker

Some environments have both single-phase and 3-phase power depending on the application. If you’re still unsure, contact your local electric contractor or utility provider.

Power Protection

Whether you’re outfitting workstations and audio/visual equipment or building a plan to protect your data center, CyberPower has you covered with a UPS system. CyberPower offers power protection solutions for both single-phase battery backups and 3-phase UPS systems, along with professional installation and service solutions.

CyberPower is your ultimate ally in power. Check out our complete selection of power protection products and service solutions. Our online tools can help you choose the right power protection for your business.

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