Single-phase vs. three-phase: what is the difference?

AC power can be divided into single-phase and three-phase. In general, single-phase power is used where the electricity demand is low. In short, single-phase is usually used to run small equipment, while three-phase has a high electrical load and can run large machinery in factories. The main difference between single-phase and three-phase is that the former is used for domestic power and the latter is used to run heavy machinery. Below I will introduce the differences between them in more detail.

1. In a single-phase connection, the current passes through a single conductor. A three-phase connection consists of the three separate conductors required to transmit the electricity.
2. In a single-phase supply system, the voltage can be up to 230 V. In a three-phase connection, however, it can withstand voltages of up to 415 V.
3. To smooth the current over a single-phase connection, two separate wires are required, one representing the neutral and the other the single phase, which is necessary to complete the circuit. In a three-phase connection, the system requires a zero wire and a three-phase wire to complete the circuit.
4. More power is transmitted on a three-phase connection than on a single-phase supply.
5. As a single-phase connection has only one phase wire, if the network fails, the entire power supply will be interrupted. However, in a three-phase power supply, if any change occurs in one phase, the other phases will still work.

Which one is better? Single-phase or three-phase?

For practical applications, the choice of phase number needs to be judged by your needs. If you are only using it for domestic and residential use, a single-phase power supply requires only a small amount of power to run your mobile devices and household appliances for your daily needs. However, when you are running three or four air conditioning units, double-door refrigerators, and extra-large washing machines at the same time, it is recommended that you use a three-phase power supply to properly distribute each load.

Conclusion

Both single-phase and three-phase power supplies have their characteristics. Generally speaking, the choice of single-phase or three-phase power supply is based on your use environment, the use of demand as a starting point for consideration, there is no best, only more suitable for you.