What is The Difference Between Single Phase and Three-phase?

What is the difference between charging an EV through a single-phase and three-phase setup?
If you have heard the words ‘three-phase’ and ‘single-phase’ being thrown around when it comes to charging your EV, you might like to know what it means.

What is the difference between single-phase and three-phase electrical setups when it comes to charging an electric vehicle?

Single-phase setups and three-phase setups actually refer to two different kinds of AC (alternating current) power system supplies:




●      In New Zealand, single-phase power is the most popular form of electricity supply used in residential properties and homes.

●      Single-phase power setups have only one power wire and one neutral wire with current flowing through them.

●      One wire has current flowing through it.

●      Because of the system structure of a single-phase setup, the system experiences power peaks and dips which change continuously during the cycle.

●      Most homes are wired with single-phase power setups. Single-phase homes have one black rectangular fuse box.

●      Single-phase power units have one main switch.



●      Three-phase power systems are found in areas where more electricity power is needed, such as business parks and industrial complexes.

●      In three-phase power setups, there are three wires and all 3 wires have current flowing through them.

●      All 3 power wires carry the load.

●      A three-phase setup is steadier and can therefore carry a higher load.

●      Three-phase power systems are found in commercial buildings; data centres; power grids; water and aircrafts; telecommunication towers.

●      Three-phase setups use three black rectangular fuse boxes.

●      Three-phase power units have 3 main switches.

Do I need a three-phase power setup to charge my EV at home?

Do I need a three-phase power setup to charge my EV at home?

The short answer is no. If you do have access to a three-phase power setup to charge your EV, it is preferable but definitely not essential.

Here are the reasons why three-phase power systems are more convenient when it comes to charging your EV:

  • Speed - a three-phase power system charges an electric vehicle faster.
  • Multiple charging points - you can increase the number of vehicles that can be charged at the same time when you have access to a three-phase power setup.

Because most residences and homes are limited to a maximum electricity power rating of 7.2kW and a maximum power grid connection of 63 Amp offered by single-phase setups, they will charge an EV more slowly than a three-phase setup.

Three-phase setups can offer higher power ratings. As EV batteries become bigger, and homes and residential complexes possess more than one electrical vehicle, charging options will require more three-phase power setup options.

When you need to charge your EV, it will be dependent on the vehicle’s onboard charger rating and the amount of electrical power supplied to the EVSE (electric vehicle supply equipment).

If you want to know more about the speed and multiple charging options offered by three-phase power setups, please contact us to know more.