What is single phase and three phase power?
All houses have single phase 240V power supplied. A/c units up to say 12 kw come as 240 V single phase units. The larger a/c units over say 14 kw are generally supplied as three phase 415V. This is to allow the high starting currents to be spread over three phases rather then one. Three phase power must be installed to the premises if a three phase unit is supplied.
