When I was an apprentice in an iron foundry one of my jobs was to start the big extraction fans (250hp)Star-delta is used just for starting large motors, where the start-up current would be too much for the supply to handle without tripping (e.g., a motor driving a large fan).
Hello Simon,
actually there has been 2 phase in the past each phase being 180 degrees apart. However 415 volts two terminal is referred to as single phase.
Alec
Correct me if i'm wrong, but what you describe as 2 phase at 180 degrees, is used in the States now, but is correctly described as split phase, and gives (in the case of the US) 120v.
And in the UK to provide on-site 110V, which is split 55-0-55 to earth.
Mishka, can you explain how that works?