The Stovebolt Site Forums The Shop Area The Tool Chest air compressor !

A local business has put an industrial air compressor out in their yard for sale. It has a Lincoln 25hp/230v/3phase electric drive motor, a Quincy 2 cylinder compressor, and a 200 gal/200 psi tank. The price is right so, What should I look for and how can I test this thing to make sure it works. Also, what do I need to do at home to make the 3 phase electrical motor work right...Thanks for your help...Tom.

Tom,

Forget trying to get that 3phase 25 HP motor to run on household current. You will need at least 300 Amps of single phase current and a rotophase to generate enough current to start that motor. You are better off going with a good quality 5 HP single phase motor (e-mail me if you want one) and a smaller motor pully to get the compressor speed down. I have such a unit in my shop now. It isn't as big, (started life as a 15 HP 3-phase w/100 gallon tank) I ran it with a 5HP single phase Baldor motor for several years before putting a 5HP 3-phase motor on it just a few months ago. Have painted a few cars / trucks and it still runs every day of the week now. The industrial Quinceys are easy to get parts for too to rebuild if neccesary . . . should last you forever if you fix it up and take good care of it.

25 Horse, my god! Anyway, isn't there a way to run 3-phase off single phase by running another electric motor in the circuit that acts as generator or something for one current phase? An old weld shop I used to go to did that to run his one big wire-feed unit or something. It's an Unofficial jerry-rig,but seems to work. Think someone on this page listed a place with plans for doing that or ? Ask in Lounge.

You will either spend huge amounts of money to try and get it running or you will kill yourself. I wouldn't mess with it unless I had a place with commercial electrical service.

GL, there was a good discussion about phase convertors awhile back.Do a web search of phase convertors, lots of info.A 25 HP 3 phase motor running at 230 volts draws 68 amps. 3 phase delivers 1.73 times the power at the same amperage as a single phase, so get out the calculator. figure 300 amps like Ken for the momentary current inrush to start the motor, that motor will blow the utility companies line fuse in a NY minute.In fact, starting a 10 hp single phase industrial 230 volt motor(50 amps running current) is a problem in a residential area.Industrial electrial motors draw almost twice the current of the typical compressor motors found on residential /commercial equipment.

Thanks, guys, for your help. I did a search and found lots of great info. I've been wanting to get one of these for a long time, and just want to make an informed decision, but then it seems to take me forever to do so. The price is right, so I may just bite the bullet and get it. Thanks again...Tom.

You can always use it to hang your coat.

I changed a Curtis three phase over to gas powered Wisconsin v-4. Plenty of power for it.