I Just Got a New Air Compressor

[Iplayfarmer]

I did some trading on Craig's List and ended up with a BIG air compressor. Now I just have to get it working.

The compressor head is a Ingersoll Rand 234. I've seen specs on the internet ranging from 10 CFM up to 19 CFM. My guess is that is depends on the size of motor that's on it. Right now it has a 2HP Baldor M3609 motor on it. There are two problems with this motor... 1) It's severely underpowered for that compressor head. 2) It's a 3 phase motor and I only have single phase power at my house.

What size motor should I get? I've added up my peak air consumption, and I think 12 to 15 cfm will give me plenty. I've tried to find some technical specifications on this compressor head, but I'm coming up with very little. I'd like to know the pressure range, torque requirements, and recommended RPM. I'm sure I can run this compressor on a smaller motor if I have the torque right. I just wouldn't get as much CFM. If anyone has a good source for tech specs on this compressor head, please post.

 

[unfinished]

I had one of those. I have a parts list that I got from the supplier of a reed valve kit when I had to replace them. Parts list shows 1.5, 2, and 3hp motors utilized for this unit. It is a two stage pump, should be around 150-175 psi.

 

[unfinished]

Army manual has 234C2 model, 610 rpm, 5CFM (which seems low)

http://www.liberatedmanuals.com/TM-5-4310-348-14.pdf

When changing motors, keep same rpm and frame type. Eitherwise you may need custom pulley size and mounting plate.

 

[Midniteoyl]

Looks smaller than my 30gal Sanborn with 3hp... I would say 3hp is max at prolly 6-8cfm @ that high PSI

 

[Iplayfarmer]

Thanks for the replies. I guess the consensus on a lower CFM is good and bad. Good in that a smaller motor will be cheaper, but bad in that I was so excited for lots of flow capacilty.

Is there some way to measure the capacity of a pump head?

If a 2hp motor really is the right size for this compressor, I may just pull the motor off my old Sears that has a bad compressor and use it for now.

 

[Stimw]

I can't tell from the pic but I'm guessing that is an 80 gal tank which means you will have plenty of air storage. Just make sure you don't have leaks and have a shut off at the tank.
I have a 5hp on a 30 gal tank and a 60 gal back up tank with shut off when not used if I need more storage. I have it set at 170 psi off 130 psi on and I never run out of air.
I would reccomend a 5hp motor, not one of the small motors you see but a real 5hp. The small motors rate them at "peak Hp" not true hp.

A lot of compressor manufacturers will use the same pump with different motor hp/pulley combinations and rpm. You could have a 5hp, 7.5 hp or a 10hp on the same pump with different size motor pulleys.

 

[BukitCase]

5 HP Single Phase Baldor Electric Compressor Motor 184T Frame L8430T 230 Volt | eBay

I recently replaced a fried (bearings, then armature) Baldor 5 horse on my 80 gal. 2 stage dev-air - the above is likely the best price you'll find, and that motor is a little better rated than the original on my compressor.

Also, the people on that link were very helpful and I got the motor in 3-4 days to the west coast. (free shipping, too - if you think this isn't important, try LIFTING a 5 horse REAL motor :=) Steve

 

[BukitCase]

Sorry, forgot to mention - if you move up to a 5 horse, or even 3 - you'll need to get one of these while you're at it

New 5 HP Single Phase Magnetic Starter Motor Control | eBay

Same people, one stop shopping

Without a motor starter (contactor) you'll be replacing the pressure switch REALLY soon... Steve

 

[Midniteoyl]

80 gal tank???? Looks smaller than that!

 

[Iplayfarmer]

I do have a few very nice hazardous duty mag starters that I can use, so that's not an issue. (I'll trade you a few nice hazardous duty mag starters for a good 5 hp single phase motor.)

I looked at the motor that's on my other compressor, and it's only 1.5 hp and it's a 3600 rpm motor. That won't work. I have another short term solution, though. It's a 1.5 HP single phase motor that is 1800 rpm. It's an old beast from back when horsepower was really horsepower. The problem is that it's turning the wrong way. If I can get it to turn the right way I may not get lots of air out of the compressor, but the compressor will be quiet.

How do I reverse the direction of this motor. It has a green, black, red and orange wires. I've attached a picture of the plate. 220 volt wiring includes the red and orange wires connected to each other with the black to L1 And the green to L2. This turns the motor clockwise. I need it counterclockwise. (110 volt wiring includes the black and orange to L1 And red and green to L2). Do I connect the black and green together and connect the red and orange to the hot wires?