The Difference Between Single Phase and Three Phase UPS Systems

For those who are doubtful about the differences between single and 3 phase UPS systems, and which is more suitable for your power supply needs, here is a short overview of the main differences and usages.

Single-phase UPS systems

A single-phase UPS consists of a single sine wave input and is typically a single phase of a larger 3 phase supply. A common example of this would be a local 3 pin UK socket which uses 230/240 VAC (UK Single phase) to supply power. Most short power hardware including rack-mounted servers, telecoms, network switches, computer systems, or any equipment operating from a standard 3 pin UK plug, work from a single-phase supply. 

3 phase UPS power supply

A 3 phase installation uses the full 3 phases which are produced from the grid. A 3 phase electrical supply comprises three individual sine waves and can be installed as either a 3 wire or 3 wire & neutral configuration. A three-phase source would typically come from a local transformer, with the standard three-phase voltage being 400/415 VAC (UK 3 phase). 3 phase UPS systems are normally used in larger installations such as data center ups, clinical care & large industrial power applications. All 3 phase solutions will require UPS installation to a 3 phase distribution board, which is normally achieved via a bypass switch facility.

Single-phase vs three-phase UPS- what’s the difference and how to choose?

When buying UPS for your business or organization, many factors should be taken into consideration, among which the choice of power supply between single-phase UPS and 3-phase UPS is the foremost one. Though both UPS offer constant backup power for dealing with unexpected situations, they have various roles. 

What is the phase in electrical terms?

If you are new to the world of electrical power, you may understand little about the term phase. Phase, at its most basic, is the distribution of electrical power, which describes the alternating current (AC) power supply alters concerning the time. There are one-phase, two-phase, and three-phase power supply types. Single-phase is commonly called “residential voltage” because it is generally available in homes. For example, the microwave oven, the coffee machine, your PC in your household can be single-phase devices. In various regions there is a similarity for single-phase connections- It requires two wires (one voltage wire and one neutral wire) for creating the circuit. 

What’s the difference between single-phase and three-phase UPS?

The key difference between single-phase UPS and three-phase UPS are the following points-

Conductor: The number of the conductor in a single-phase and 3-phase system is different. Single-phase UPS contains one conductor while 3 phase UPS supply power through three conductors.

Sine wave: Single-phase UPS provides a single sine wave, while 3 phase UPS gives three sine waves, each out of phase and spaced 120° apart from each other.

Voltage: Single phase voltage is 120V in North America, while the phase to phase voltage for a 3-phase system is 220V, and the phase-to-neutral voltage is 120V.

Maintenance: The plug-and-play feature of single-phase UPS makes it easier than a 3-phase counterpart to install and set up without the need for outside installation.

Efficiency: For low power requirements, single-phase UPS is more efficient than 3-phase UPS. But when the power demand is higher, 3 phase UPS shows more capability to carry a greater load more safely.

Expense: The equipment in a 3-phase UPS system will have longer life expectancies and the transmission lines for 3 phase power do not require, heavy scale copper wires as single-phase UPS, thus, in the long run, 3 phase UPS will save more money.

Application: Single Phase UPS units are available in those applications with lower kVA requirements, usually less than 20kVA, such as homes, small businesses, and satellite offices. 3 phase UPS units are usually used in large installations, such as data centers, and large industrial power applications with higher power requirements.

How to choose?

Whether a single-phase UPS system and a 3-phase UPS system should be chosen depends on the power requirements of your applications as well as what power source the equipment is connected to. You will need to verify the load the UPS will protect and obtain their voltage range. Usually loads less than 20kVA can securely use the single-phase UPS, or larger loads tend to use 3 phase UPS. Once you determine the 3-phase UPS, the downstream loads that the UPS protects will judge whether 3/1 UPS or 3/3 UPS is the most suitable one. 

A  power failure can perceive you wasting hours trying to find out what the problem is and going over any work you may have lost. If customer data is affected, you might have to spend wasted hours making apologies and correcting the situation. At Right Power, we are proud to say that we provide backup power supplies for a range of clients across a whole spectrum of industries, including data centers, healthcare, and telecommunications. So whether you need a single-phase or 3-phase system, you can trust our years of experience to provide you with the backup power you require. Visit our official website to see the best ups suited to your requirements.