What is 3-phase?

Three-phase is a type of grid connection. It describes how your home is physically connected to the grid. All grid connected homes in Australia are either:

single-phase, two-phase, orthree-phase
Single-phase: Most Australian homes have ‘single-phase’ electricity. This means that they have one live wire to their home carrying all their electricity. If you have single-phase, you can ignore this post and carry on with your day.

Two-phase: Two-phase supplies are rare, but some people have them. Two-phase means there are two live wires going into your home. If you have two-phase – you need to read this post as 2-phase battery systems have similar issues to 3-phase battery systems.

Three-phase: As people get bigger homes and more powerful appliances, such as large air conditioners and pool heaters, they may need more power than can flow down a single wire. For this reason, more and more homes are getting ‘three-phase’ connections. three-phase means that you get three live (or active) wires instead of one. It follows that you can have three times the power coming into your home. If you have three-phase power, the phases are red, white1 and blue. Your single-phase appliances run off one of those phases. Any large, three-phase appliances connect into all three-phases. As electric cars become common, more people will start to upgrade to three-phase so they can charge the car more quickly.