wattage for a 3 1/2 air compressor?

by darrell
(palm bay fl)

i have a 3 1/2 horsepower 10 gallon tank and was wondering what size generator ill need to have it run properly


____________________
Darrell, according to www.google.com/intl/en/help/features.html#calculator, 1 horsepower = 745.699872 watts

I am not an electrician nor a motor mechanic so my advice is suspect. Yet, is it logical to think then that you will need at least 2500 running watts? Inrush will require more.

Any electrical gurus out there can help Darrell?

Cheers,

Bill


Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Electrical-troubleshooting-compressors.

Air Compressor Wattage Requirement

How large a generator (portable) do I need to adequately power a 230V/20Amp Air Compressor, Single Stage, V Head 3hp?

Comments for Air Compressor Wattage Requirement

Click here to add your own comments

Apr 19, 2008
Generator for portable compressor
by: Jim

I'm not an engineer...but here goes:

P=EI for the power formula in watts

Therefore, 230 * 20 = 4,600 watts that your generator will need when running.

However, a compressor is a inductive load device, and the same as a fridge when it first comes on, lights dim and there's a power inrush until the motor comes up to designed speed. So while it comes up to speed it sucks more current than at normal running speed.

And this lower run current (start up inrush) must be factored into the generator's size.

Honda.ca show this in their generator chart.

So you will wind up selecting a generator bigger than the compressor's running watts to cover the start up load, and then maybe go to the next size bigger for winter compressor use when both the generator oil and the compressor oil is thicker - it could use the next size up to handling the load, help like having a big V8 under the hood, even though a 6 cylinder might do the job.

Jim

Click here to add your own comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Electrical-troubleshooting-compressors.

Voltage converter,step down and up. 220v to 110v.

by Rich

voltage converter,step down and up. 220v to 110v.






Bill wonders...

Hi Rich:

First off, my apologies for the lateness of the response. I've had an email problem that seems, I hope, to be resolved now.

Second, I'm sorry. I'm not getting the question?

If you are looking for a source, I suspect you'd need to supply more information to a vendor. For example, what's the application. What kind of amperage will be required...and so on.

Although my advertisers may be able to sell you products, I don't actually sell compressed air equipment from my site.

I'm not sure where you are located, but if it helps, here's one source of transformers.

Cheers,

Bill

Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Electrical-troubleshooting-compressors.

hooking a new moter to my old compressor - how bad did i screw it up?

by rex becker
(richmond Texas usa)

I was hooking a new moter to my old compressor, the new moter could run 120 or 220 and i missed swaping one of the wires in the moter. plug it in and got buzzing. unpluged it found my misstake and move the other wire, plug it back in and got nothing! What did i smoke and can it be fixed and how can i check it, i don't have a moter wiring schmatic to ohm it out.

Click here to post comments

Add your own question or comment. It's easy to do. How? Simply click here to return to Electrical-troubleshooting-compressors.