Shop air compressor amperage question

[FOMOGO]

Looking at buying a new compressor for the shop. I am looking at 2 compressors from the same manufacturer both 2 stage 175 psi with 7 1/2 hp motors. The question is about amperage requirements. One calls for 230 volts and 40 amps while the other calls for 230 volts and 32 amps. I cant see any difference in the 2 except the amps required and of course price. Both are 24 CFM at max pressure. One has an aftercooler, a good thing, and the other does not.

Can anyone shed some light on what might be different? The first one is "fully packaged" while the second one is the "Base model".

https://www.zoro.com/ingersoll-rand...or-2-stage-24-cfm-2475n75fp-230-1/i/G0694197/

https://www.zoro.com/ingersoll-rand-electric-air-compressor-2-stage-24-cfm-2475n75/i/G2885382/

 

[Studeman68]

Looking at buying a new compressor for the shop. I am looking at 2 compressors from the same manufacturer both 2 stage 175 psi with 7 1/2 hp motors. The question is about amperage requirements. One calls for 230 volts and 40 amps while the other calls for 230 volts and 32 amps. I cant see any difference in the 2 except the amps required and of course price. Both are 24 CFM at max pressure. One has an aftercooler, a good thing, and the other does not.

Can anyone shed some light on what might be different? The first one is "fully packaged" while the second one is the "Base model".

https://www.zoro.com/ingersoll-rand...or-2-stage-24-cfm-2475n75fp-230-1/i/G0694197/

https://www.zoro.com/ingersoll-rand-electric-air-compressor-2-stage-24-cfm-2475n75/i/G2885382/

Doug, I agree with you, I can't see any difference except for the aftercooler also. I'm wondering if the lower priced model has a different model motor on it? Seems like a big difference in price for just an aftercooler....

 

[FOMOGO]

Doug, I agree with you, I can't see any difference except for the aftercooler also. I'm wondering if the lower priced model has a different model motor on it? Seems like a big difference in price for just an aftercooler....

It also has the automatic drain for what that is worth. I have a couple of automatic drains sitting on the shelf so that is not a selling point to me. And I hate to hear them when they dump air. My neighbors don't want to hear it either...

I would like to know why one is right side and the other left side configured. Seems odd to make that much of a change.

 

[Studeman68]

It also has the automatic drain for what that is worth. I have a couple of automatic drains sitting on the shelf so that is not a selling point to me. And I hate to hear them when they dump air. My neighbors don't want to hear it either...

I would like to know why one is right side and the other left side configured. Seems odd to make that much of a change.

Looks like some of the dimensions are different too...

 

[Studeman68]

Looks like some of the dimensions are different too...

This ones cheaper straight from the maker.. free freight too;

https://www.ingersollrandcompressedair.com/2475N75-V-Two-Stage-Cast-Iron-Air-Compressor_p_19.html

 

[SAT]

I’ll check tomorrow and update. Ingersoll Rand here as well.

 

[chrisr]

This ones cheaper straight from the maker.. free freight too;

https://www.ingersollrandcompressedair.com/2475N75-V-Two-Stage-Cast-Iron-Air-Compressor_p_19.html

Looks like there is a $75 lift gate fee, wonder if free is to a dock?

 

[Havasu Dave]

The disparity in amperage listings is due to misquoting in the specifications. They both use the same motor- rated at 32-35 amps depending on voltage, 208 or 220. Definitely nothing stated in either spec list that would account for the disparity. I'd give their sales rep a call and inquire.

 

[steven Durham]

Hello are you locked in on the Ingersoll Rand brand I have a Chicago Pneumatic and although it is a small it was rated higher than the Ingersoll Rand.
The post by Havasu has merit and having a quality Amp Meter around is a good investment.

 

[SAT]

Same model #2475, 7 1/2 hp. No aftercooler, but in a pretty moisture proof, well insulated, climate controlled shop. 6 mil plastic under the heated slab floor. No painting and only spot blasting or a little more.
So, very different climates as well, to your location. The auto drain works once in a while
I forgot to check the breaker, it’s probably matched to the peak start-up amps. We probably should have mounted the mother board on the near-by wall and not on the main chassis, less vibration.
If the shops in your area have aftercoolers , I would follow their lead.
Hope this helps
Steve

 

[FOMOGO]

Same model #2475, 7 1/2 hp. No aftercooler, but in a pretty moisture proof, well insulated, climate controlled shop. 6 mil plastic under the heated slab floor. No painting and only spot blasting or a little more.
So, very different climates as well, to your location. The auto drain works once in a while
I forgot to check the breaker, it’s probably matched to the peak start-up amps. We probably should have mounted the mother board on the near-by wall and not on the main chassis, less vibration.
If the shops in your area have aftercoolers , I would follow their lead.
Hope this helps
Steve

Thanks for the info Steve. My current 2 stage doesn't have an aftercooler and I don't typically fight water. Just drain the tank on occasion. The very reason the auto drains are still on the shelf. I also have 2 refrigerated dryers that I haven't bothered to hook up... I do plan to build a shelf and mount one of them above the compressor with a separate system plumbed through it for extreme dry air needs. If I get around to it... The blast cabinets are across the shop and have close to 100 feet of line run. I never have more than a few drops of water when I drain the dryers, which I do every time I use the cabinets.

I don't open my building up often so I don't get outside moisture inside. Stays pretty consistent humidity wise. Don't have to fight rust on bare metal and the like.

 

[outlawamps]

1) Without seeing the data plate on the motor, my guess is that one spec is giving the actual amp draw (32A) and the other is giving the required circuit protection (40A). That compressor will likely draw 120A or so instantaneously on start-up, but will quickly settle.

2) Go with the Ingersoll.

3) As for moisture, I have my compressor in a second building next to my shop. I ran 3/4" copper the whole way, as well as a fabricated copper water trap at the compressor (inlet top right, outlet lower left), and a second smaller trap (no pic) just before it goes underground to my shop. All that copper gives the air ample time to cool down and normalize... I have zero moisture issues with this set up and it's really quiet since it's remote, not to mention zero leak problems. Whatever you do do not use pvc.