Discussion in 'General Electronics Chat' started by stephasbury, Jul 6, 2009.
Is it possible to have a 3 phase system and 240 volts?
very common here in North America
Very common here in the UK too. Most medium and large premises have their 230V delivered as 3 phase and then distributed in the building as single phase 230V.
I have been looking for a piece of medical equipment that is 240V and a 3 phase system. All of them are 208V and 3 phases, I'm having no luck.
Get a quote on having the 208 service pulled to where you need it. You'll almost certainly have it serviced to your building.
There is an interesting thing about 3 phase. If you have a Wye arrangement with all three phases to a common line, you have 240 volts. With a delta arrangement, you measure only 208 volts. That is because the phase angle from one to another is only 120 deg. The sine of 120 degrees times 240 volts is 207.8 volts.
Check further - you may be able to use this equipment.
A wye system(3-phase+neutral) having phase-neutral voltage of 240V is also a delta system without neutral of 415V.
The phase-phase voltage with delta connection is always 1.732 times higher than the phase-neutral voltage.
Three phase AC is a lot more efficient then single phase AC. It can provide good results over longer distances.
Check your equipment ratings carefully. Many devices will work with 208 or 240V three phase.
If all else fails and you must have 240V a dry type step up transformer can be installed to give the necessary voltage. (Be warned, this may put a considerable dent in your checkbook)