# Understanding compressor ratings



## Hydroracer (Jul 28, 2020)

I have a pretty good idea of what I want in a compressor, but as usual, nothing is straight forward.

For example, I am looking for something in the 15-18 CFM range, 5HP, 60 gallon, 2-stage. Would sure love more, but cost is a limiting factor.

However...looking at several brands, I see one that is rated at 15.3 CFM at 100 PSI, and another for only a few more dollars is rated at 15.2 CFM at 175 PSI.

Both go to 175 PSI, it's just the ratings on the first one as at 100 PSI and thesecond one is rated at 175 PSI.

Is it correct to assume the latter will provide even more CFM at the same 100 PSI as the previous one?

I guess, what I mean is, the second one will output more CFM overall?


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## stevon (Mar 5, 2019)

Hydroracer,

In theory the compressor rated at 15.2 CFM at 175 PSI should have more CFM at 100 PSI but even if is 2 more CFM @100psi that won't be a critical difference. Noise level, pump RPM, cylinder design and duty cycle are more important specs when considering a compressor. First off what is the target application? HVLP spray gun or just an air ratchet? How long will the max CFM demand be needed? 10 minutes or all day? one air tool or several at the same time? listing the models of the compressors you are considering would help as well. 

Stephen


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## Hydroracer (Jul 28, 2020)

Target application is general use. Small die grinder (1/4"), plasma cutter, 1/2" impact wrench, possibly some sand blasting of small parts, and spraying finish on small pieces.

I currently have an older CH Extreme Duty 26 gallon/2HP that has served me pretty well over the years, with the exception perhaps of the sand blasting, but it's a royal pain in the butt to drag it around every time I need it in the barn or the garage, etc. Want something bigger and permanent mounted and I can run piping where I want air.

Believe me, I'd love to go higher into a 7.5HP model for even more CFM, but I don't think my electrical system would handle it. The compressor is going in the barn which is a hundred or so feet from the house. The run goes from the house to the garage (which is between the house and the barn), then to a sub panel in the barn, then to another sub panel further back by the shop (there is a 2-bedroom apartment up in the back of the barn, but it not used so I am using it's subpanel to supply my shop). The house itself has two of the old screw in type fuse boxes, each is 60 amp, so I have a total of 120 amps (house was built in 1900).

The two compressors I mentioned as far as specs go are:









DeWalt DXCMV5076055 5-HP 60-Gallon Two-Stage Air Compressor 230V 1-Phase


Buy DeWalt DXCMV5076055 Direct. Free Shipping. Check the DeWalt 5-HP 60-Gallon Two-Stage Air Compressor (230V 1-Phase) ratings before checking out.




www.aircompressorsdirect.com





and the second one:









Quincy 2V41C60VC QT-54 Pro 5-HP 60-Gallon Two-Stage Air Compressor 230V 1-Phase


Buy Quincy 2V41C60VC Direct. Free Shipping. Check the Quincy QT-54 Pro 5-HP 60-Gallon Two-Stage Air Compressor (230V 1-Phase) ratings before checking out.




www.aircompressorsdirect.com


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## stevon (Mar 5, 2019)

Hydroracer, ,

I like the Quincy model because of the "V" block design and Baldor motor, lower RPM, definately a more industrial design. The DeWalt is a "store bought" homeowner quality level. I'm sure either will last for years as long as they are maintained. I think either model would work for your needs, it's just a preference choice.

Stephen


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