What Is Three Phase And Single Phase?

[tornadofreak15]

Hi, everyone well, i am wondering what a three phase siren is and a single phase? can someone help me out and tell me what they are and the differences and what the best choice is?

[Wdr]

Better depends on your application. For municipalities three phase would generally be preferred. Smaller wires, simpler motors, cheaper motors. However, for most siren enthusits single phase would be preferred or even required to be able to run a siren. A normal residence dose not have three phase available and all of the ways to produce it are expensive, ineffienct, or both.

[Hacksaw]

The basics of 3 phase power is covered here:

https://en.wikipedia.org/wiki/Three-pha ... tric_power

And, some one phase motor sirens consume so much power, that an average home's power service can't run then.

[TWB8s]

In short: 3 phase is generally 240v/208v from municipal utilities. Generally 480v 3 phase would be commercial. Some electricians refer to "single phase" as two legs of a three phase system (aka 480v or 240/208v single phase). Then there are other electricians that refer to "single phase" as one hot leg and a neutral (both 277v and 120/110v).

[jacob585]

just wondering is there such thing as "two Phase"?

[Snowcube]

just wondering is there such thing as "two Phase"?

Well, brushless DC motors are sometimes two phase. I also read somewhere that Dane County, WI's Banshee 110's were two phase. Can't find any evidence of this though and I have never heard of a two phase AC motor.