Why is mains voltage 230V?

Answer 1

Yes 230 volts is classed as single phase but it is not the only single phase voltage. If you take any two legs from a three phase system, the voltage from these legs is also classed as single phase. The 230 volt single phase is the output of a transformer whose primary is one leg of a three phase primary high voltage system. The 230 volt secondary is center tapped to give 115 volts before the tap and 115 volts after the tap, hence the common voltage of 115/230 that is used in North America.

Answer 2

Mains voltage in many countries is 230V to balance safety and efficiency concerns. This voltage level is considered a good compromise between the need for high voltage to reduce energy losses over long distances and the need for lower voltage to ensure safety for consumers. Standardizing at 230V also helps to harmonize electrical equipment and distribution systems across different regions.

Answer 3

About 1/2 the current. Smaller wires for same load.