Compressors - single or three phase

[Clearskies01]

I am looking at this compressor and wonder if anyone has comments on it and can explain the difference between single and three phase compressors.

http://memphis.craigslist.org/tls/4672424281.html

I know the pic may not be there long so, it is listed as a Wayne 3 phase air compressor.

I want a strong compressor for a new build and need plenty of air for blasting cabinet(s). Thx....Ron

 

[ddawg16]

Unless you have 3ph available, stay with single phase. In most cases, the only places that have 3ph are industrial areas.

 

[TTA579]

I am looking at this compressor and wonder if anyone has comments on it and can explain the difference between single and three phase compressors.

http://memphis.craigslist.org/tls/4672424281.html

I know the pic may not be there long so, it is listed as a Wayne 3 phase air compressor.

I want a strong compressor for a new build and need plenty of air for blasting cabinet(s). Thx....Ron

That refers to the electricity supplied to the motor. Single phase is what is supplied to most houses. 3-phase is generally limited to commercial or industrial facilities.

 

[Zrexxer]

It's a safe bet that if you don't know what 3-phase electric service is, you probably don't have it. In any case, that compressor looks kind of tired for $600, plus needing a $500 motor swap.

 

[Clearskies01]

I think you're right. I'm starting a new garage build in a couple weeks. I'm talking to my electrician later today about some other stuff. I'll see what's involved with, and do i want to install 3 phase in my 30' x 50' garage/shop. You're probably right.

For my info, what are the advantages of using single phase power over three phase power on a large compressor?

 

[bcradio]

single phase obviously

 

[G_P]

Depending on where you live, 3ph power may not even be an option.

 

[PBCampbell]

The advantage of single phase over 3 phase is cost. I was quoted something about $20,000 a few years ago to have 3 phase hookup even though there is a business only 300' from me with 3 phase.

 

[Zrexxer]

Three phase motors are a simpler design, and more compact and less expensive for the HP rating than a single phase. Plus, single phase motors are limited to about 10 HP, whereas three phase can produce a lot more power. But it's usually only available from the utility in industrial areas, and sometimes rural areas. If it's not already at your property though, getting it there could be expensive.

 

[fatfillup]

Also three phase pulls less amps so lighter wire can be used then on a same sized single phase motor.

I used to think 3 phase costs less to use then single phase, but I believe that is false.


Zrexxer stated he thought the compressor looked tired and normally I would say you couldn't tell that from a pic, but in this case, since it most likely came out of a company and was replaced with a shiney new one,,,,,,,,,,,,,,,I have to agree. The seller will find his market quite small for a used three phase compressor as homeowners won't have the power and a business is going to want something reliable. Of course there are exceptions.

 

[FMC1959]

I had asked the same thing for years and did some research, I still don't completely understand 3 PH, but when people say it is more expensive, we aren't talking a couple of grand. IF, you can get it at your home, it would be something ridiculously expensive, think of more than $20k. Businesses that have it have enough 3 PH motors running to recoup the initial expense

Speak to your electrician, but I don't think 3 PH is a cost effective option. I know a 3 PH runs cooler than an equivalent 1 PH, and 2 identical compressors that offer 1 PH & 3 PH, are supposed to pull the same KWH. I think the electrical company charges a lower rate being pulled for 400+ volts...or something like that.


As far as that compressor, or any you see with 3 PH, you can change the motor, I know some that have done that. Also, not sure if all, but many 3 PH motors can be hooked up to single PH