In the world of electricity, there are still lots of things that not many people know about. Usually, when dealing with electrical appliances and whatnot, we do not feel it necessary to bother much about what the electrician is doing due to the fact that we are too used to relying on the experts in helping us out.

All though there is nothing wrong with that, but it still does not hurt to know your facts when it comes to electrical components and the terms related to it, right? For today’s article, we will be discussing single phase vs three phase. Don’t know what these are? Read on to find out!

Difference Between Single Phase vs Three Phase

What is Phase?

When it comes to electricity, phase refers to the sharing of the load on a circuit network. What this means is that houses and factories usually have more than one wiring that connects all the appliances in the building to the mains line. The phase refers to the number of wires that essentially connects these two.

Single Phase vs. Three Phase

Single phase is more commonly used in houses and consists of two wires through which the alternating current (ac) flows through the power wire and the neutral wire. Of course, before flowing into the neutral wire, the current first flows through the load.

On the other hand, three phase circuits are more commonly installed in large outlets such as factories. In a three phase power circuit, there are three wires involved (hence the name).

In this arrangement, the alternating current flows through the three wires where each individual phase alternating current is 120 electrical degrees away from the next.

Let us now take a look at some of the other differences between the two wires.

1. Load accommodation

Generally speaking, single phase power circuits have a lower tendency of being able to support too many loads at once. Due to this, in modern homes, single phase electrical circuits are only used in areas where the sole loads will be due to heating or lighting and nothing heavier than that.

On the other hand, three phase circuits have a greater capacity to withstand heavier loads, and this is the main reason why they are being used more and more in large factories and in areas of the home which deal with large amounts of current (such as almost any electrical appliance).

Moreover, you will also be able to obtain a single phase power system from a three phase power system either by connecting it to a transformer in order to achieve the right amount of voltage or by doing it directly.

Which method you should choose depends on your location, and we would advise you to consult a local expert regarding this matter.

2. Power consistency

No current remains constant over a certain period of time. The phase power systems are constantly working to prevent the dips and surges of electricity from ruining our electrical appliances.

However, amongst the two phase power systems that we are discussing in today’s article, the three phase power system is more efficient at keeping the power more or less steadier than the single phase power.

For those of you who might be confused about what voltage dips and surges are, let us elaborate it for you.

  • Voltage sag

When the voltage of a power supply sags (this is just another term used by many for voltage dip), what happens is that the voltage reduces by 10% from its normal value.

This causes the voltage in the different outlets in your house to drop as well, and subsequently, if you put your phone on charge in one room, then a person in some other room will see the lights in that room growing dimmer and dimmer.

A sagging voltage usually lasts for over a minute, and the reason behind this happening may be due to your transformers getting overloaded and having smaller than required sized conductors.

  • Voltage surge

By now, you would have guessed that a voltage surge is the exact opposite of voltage sag. In this condition, the voltage in the lines goes 10% over the required value. This can bring about issues related to your machinery, and if this problem has occurred in a plant, then the whole quality of the power in the plant will be affected by a voltage surge.

Usually, you are more likely to experience a voltage surge if a large electrical appliance such as a motor has been switched off in the same vicinity as you, which results in a temporary increase in the power line.

Also Read: How To Convert 3 Phase To Single Phase 220v?


Even though we did only talk about three phase wires, which consist of only three wires, there are some three phase wires which consist of a fourth wire known as the neutral wire.

This neutral wire is very similar to the neutral wire on a single-phase power, but this still does not change the fact that a single phase is different from three phase. That was all for our article for today on single phase vs. three phase. Thank you for reading till the end!