what hp motor for air compressor needed?

[flaboy1979]

I picked up a new air compressor pump its a Ingersoll rand model 2475 it was powered by a 12.5 hp gas engine .I want to power it with a electric motor .What size motor should I use ?I have a 220v 5hp is this a big enough ?

 

[Charles (in GA)]

General rule of thumb is gas hp is twice elect horsepower for compressors.

Charles

 

[G_P]

5HP should do the trick. Look up what the rpm range on the pump is and size your motor pulley accordingly.

 

[Steevo]

A "true" 5hp motor will turn it just fine.
I used a Baldor L1410T on my IR 2475 pump when I converted it from gas to electric, and it works fine.

Here is a link to the motor I used:
http://williamsonneelectric.com/5hpbaldoraircompressorelectricmotorl1410t.aspx

 

[zkling]

5-7.5hp electric. I think it runs ~1K-1500RPM, should put out ~20-30CFM @ 90psi. ranges are respective to the HP used. You may want to call IR and have them send you a performance curve for that pump.

 

[larry_g]

http://www.garagejournal.com/forum/showthread.php?t=139111&highlight=compressor

http://www.garagejournal.com/forum/showthread.php?t=139593&highlight=compressor

Steevo did a couple of threads on this. In the first thread above I responded a couple of times with links to some pump information. One important thing I remember is that the gas and electric pumps turn in different directions. A second thing to know that this pump is rated for a wide speed operating range. The speed you drive it at is relative to the HP of the prime mover. Two important things to avoid are overcurrenting the motor and underspeeding the pump.

lg
no neat sig line

 

[stonesfan68]

The flywheel is different between the gas and electric compressors. This is not so important as long as you don't mind hot air being blown at you during operation with the electric motor.

The 2475 can be run with a 5HP or 7.5HP motor.

Pump RPM = 1040
HP = 5.5
Max PSIG = 175

Pump RPM = 1500
HP = 8.2
Max PSIG = 175

Minimum RPM = 575
Maximum RPM = 1600
Compressor sheave OD = 13.75 inches
Compressor sheave PD = 13.5"
"A" belt section

I'd use a 7.5HP motor and a 5HP motor pulley, personally, but that's just me being a compressor-head.

 

[Ross/Kzoo]

I have heard, but not investigated it, that compressor motors have different characteristics than regular motors.