Should You Get A 3 Phase Inverter?

solar panels in the roof

First and foremost, what is a 3 phase inverter? A 3-phase solar inverter receives DC electricity from solar panels, segments/divides it, and redistributes it as AC electricity across a three phase supply. Within Australian homes, the majority would use a single-phase supply. This means there is one wire coming in from the grid. A 3-phase supply will have 3 wires coming in from the grid. What this means is that homes with 3-phase supply can receive more power from the grid. A 3 phase inverter is especially helpful for those who want to use solar power. Three-phase inverters have many benefits but are more expensive. You must know these benefits and their relation and relevance to your own home, before making the choice to buy one.


Why is it good?

By spreading the inverter’s capacity across three-phase supply wires, solar power does not have to work as hard to get out to the grid. By using a 3 phase inverter, you will be increasing the amount of voltage less than a single-phase inverter, which results in decreased trips due to over-voltage. The result of this is the steady solar power generation, minimizing issues to do with over-voltage. The solar power generated is converted into AC electricity, which is then evenly distributed across the property. For example, a single-phase would be working hard to distribute power into one phase, whereas a 3 phase inverter would distribute the power evenly across 3 phases. It is important in relation to solar power, as a solar power system can be large (over 6kw), and all that power being distributed into a single-phase can unbalance the system. Using a 3 phase inverter allows the even distribution of power and steady balancing of the solar power system.


Should you get it?

two men installing solar panels in the roof

If your meter’s wires are thin, from meter to grid, then you may have run into the recurring issue of high voltage drops. The 3 phase inverter spreads the electrical power across 3 phases, resulting in a 3x decrease in voltage drop, on each wire. If you are regularly running into the issue of voltage drop on your wires, then the installation of a 3 phase inverter may be a good idea to solve this issue. If you do not have skinny wires coming from the meter to the grid, then you will have the choice between single-phase and 3-phase. Whether you choose either one is up to you. 3-phase has the advantages of being a more stable and robust system, with lower voltage drops and much more balanced, however, it is more expensive than a single-phase. It is worth mentioning, as mentioned above, that any solar power system at or above 6kw should use a 3 phase inverter to evenly distribute power that is being converted (from solar to AC electricity), in order to keep the system balanced.


In conclusion, a 3 phase inverter is recommended if you have a 3-phase power supply, as it comes with many benefits, including reducing voltage drops and over-voltage issues related to skinny wires, as well as keeping a more balanced and distributed, stable power system. Furthermore, it is recommended for larger (>=6kw) solar power systems, to keep the system stable and power distributed evenly, as the solar power converting to AC electricity and flowing through one phase can unbalance the system. Thus, a 3 phase inverter is recommended for this reason. The 3 phase inverter is usually much more efficient and effective for any situation as mentioned above and is worth forking out the extra $600~ to install it into your house if you have the required 3 phase power supply that is needed as a prerequisite to implementing the 3 phase inverter system.