Converting 3ph. compressor to 1ph?

[CUSTOMMANCAVES.COM]

How easy/hard is it to convert a 3-phase compressor to single phase? Just swap out the motor?

I see a ton of 3ph. compressors on Craigslist and they're typically cheaper than the single phase units, plus they seem to sit for awhile. I assume this is because 3ph. units are more difficult to sell (smaller market/demand)...

Looking in the $700 range.

Here's one ad that got me thinkin'... http://miami.craigslist.org/brw/tls/2211410847.html

And another: http://miami.craigslist.org/brw/tls/2214134005.html

 

[Daddy_Rabbit]

you can build a "pony motor" style converter or purchase a phase converter - either rotary or digital.

Or, you could change the motor out, but normally you will have a difficult time finding a single phase motor bigger than 5 h.p.

 

[cwlo]

I did exactly that. Purchased a barely used Champion 5hp 3 ph for $500, and then purchased a single phase 5hp Baldor motor. There is a seller on Ebay that sells them new for just over $300. I then strung some larger 12 ga wire from the pressure switch to the motor. The magnetic switch had settings that needed to be adjusted since the amperage is higher on single phase. I would guess that some magnetic switches are not that adjustable, so you might have to buy a new one. Here again, check Ebay for good pricing.

Chris

 

[DCarr]

http://www.phoenixphaseconverters.com/

 

[CUSTOMMANCAVES.COM]

http://www.phoenixphaseconverters.com/

Well...that shoots a big hole in my "save money" theory.

So, the problem seems to be that a 3ph. motor can't easily/economically be swapped out with a single ph. motor?

 

[Norcal]

http://www.phoenixphaseconverters.com/

Phoenix would not be on my short list of RPC manufacturers.

 

[Lhorn]

Like the guy above, I did the conversion with an Ebay motor. After paying a bit over 300 for the motor on an auction, shipping for the motor, upgrading a bit of wiring and a new "heater" for the magnetic starter, I have about $400 into doing the conversion. So it only makes sense if you are getting a great deal on the 3 phase compressor.

I'm not sure what compressor you are looking at but if it's late model 80 gallon with a true 5 hp 3 phase motor, you might be able to talk him down a lot. Mine is a late model Speedaire. I'd pay a bit more for a premium brand like Champion.

The guys asking a lot for 3 phase compressors either don't need to sell or are unrealistic. Offer a lot less. With the economy the way it is, it's a buyer's market on 3 phase stuff.
I'm not a fan of lowballing, but when I saw the ad for mine I called to find out it is 3 phase (didn't put that in the ad). I said that it would cost me too much to do the conversion at his asking price of $700. I suggested to him to try to keep selling it at his price, he might get it, but if he ever can't sell it and would accept $400 give me a call. He took the $400 offer pretty quickly.

 

[fordcragar]

I bought a IR Type 30 3-phase compressor a couple of years ago for $300. Picked up a 5HP Baldor single phase motor off of Ebay for under $300 (shipping included). It gave me a nice compressor with a 80 gallon tank for under $600.

 

[klhitman]

I will say it again just put VFD on it and you won't have to worry about the starter or changing out the motor and run the P switch to an input on the VFD and you are done.


http://www.joliettech.com/abb_acs15...types_voltages_construction_prices.htm#240vac

 

[Norcal]

A/C Drives (VFD's) over 3 HP are expensive, in most cases a 10 HP 3Ø drive is used that can have phase loss protection disabled to run a 5 HP 3Ø motor on a single phase supply.(Derated 50%). A 5 HP 1Ø motor will be cheaper then a VFD.

 

[patrick66]

Three-phase can not be used in a residential application, only in a building zoned for ag or industrial/commercial. This is why you won't see a 3-ph anything in a home shop or garage.

That's my understanding from local electricians.

 

[CUSTOMMANCAVES.COM]

Three-phase can not be used in a residential application, only in a building zoned for ag or industrial/commercial. This is why you won't see a 3-ph anything in a home shop or garage.

That's my understanding from local electricians.

My shop is commercial, but I don't have 3-phase service. It's available, but I don't really need it for my work. I do need a compressor, though.

 

[fordcragar]

If you are considering a VFD, you will need the match the amperage of the motor with the VFD amperage output. When I was thinking about a VFD, it's cost would have been greater than the new single phase motor.

 

[CUSTOMMANCAVES.COM]

If you are considering a VFD, you will need the match the amperage of the motor with the VFD amperage output. When I was thinking about a VFD, it's cost would have been greater than the new single phase motor.

Not considering it. Looking for a cheap way to convert a 3ph. compressor to 1ph.

 

[Norcal]

Not considering it. Looking for a cheap way to convert a 3ph. compressor to 1ph.

Find a 1Ø motor.

 

[hetkind]

To get three phase into my shop has been priced out at 250k, since new wires have to be strung over a mountain...

However, you can get a NEW IR 2340 dual stage, 220v single phase at 17 cfm for about $1,100 delivered to your door.

Howard

 

[Climber]

I will say it again just put VFD ...

VFD way to go!!!

Three-phase can not be used in a residential application, only in a building zoned for ag or industrial/commercial. This is why you won't see a 3-ph anything in a home shop or garage.

That's my understanding from local electricians.

False

Not considering it. Looking for a cheap way to convert a 3ph. compressor to 1ph.

Not considering? Why? VFD is the way to go if you have 3-phase motor and 1-ph feed. You NEED to learn more about VFD to understand how MUCH you can benifit from it.

Here is scenario:
You got compressor 5Hp 3-ph, 17 CFM, 1,000 RPM. You pay $700
buy new motor $270-350 or VFD $350-500
What you get for extra money?
1. you dont need mag starter. VFD starting motor smovely, It can be set how smove it starting motor. For example: 5 seconds Amp curves from 0 to your max.
2. You can set VFD to run compressor instead 1,000 RPM to lets say 650 RPM (do not run less then pump specs). You don't load wire, motor, compressor. It runs quietly and longer. Less stop and start.
3. Occasionally, if you need full or more CFM, you can set VFD to run faster from 1,000 RPM to lets say 1,200 RPM (see if compressor capable of doing this) so now you have not 17 CFM you got 20.4 CFM.
4. VFD is robust as volume control in your iPod, you need to learn first all capabilities before denying.