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cuemaker
04-07-2010, 05:51 PM
My current motor is quite old. Its a 1.5hp (10.something amps) induction motor that overheats on my compressor after a few cycles (it had burnt windings when it came with the compressor).

My compressor head is an old 2 stage Worthington. I am not sure what the RPM is supposed to be, but I am sure its not supposed to be high...

Should a 3hp (amps listed at 15.4-13.7) do the job since I have a 10 amp motor doing it now?

Also, do I want an induction motor or a start capacitor motor? They are roughly the same price..

squirrel
04-07-2010, 07:00 PM
My current motor is quite old. Its a 1.5hp (10.something amps) induction motor that overheats on my compressor after a few cycles (it had burnt windings when it came with the compressor).

My compressor head is an old 2 stage Worthington. I am not sure what the RPM is supposed to be, but I am sure its not supposed to be high...

Should a 3hp (amps listed at 15.4-13.7) do the job since I have a 10 amp motor doing it now?

Also, do I want an induction motor or a start capacitor motor? They are roughly the same price..
What is the line voltage and single or 3 phase?
Have you verified the unloader is working?

KiddZimaHater
04-07-2010, 07:03 PM
It sounds like your old motor is 110v, single phase since it was drawing 10 amps.
I would go with a 2 horse motor, 1750 rpm, but I would wire it for 220v to draw less amps and run smoother.

Forrest Addy
04-07-2010, 07:40 PM
Look before you leap. Try to find out what the reccommended HP that particular compressor pump absorbs at a given RPM . If you can find the make, model and S/N you shouldn't have too much trouble tracking down the data.

Alternatively, determine the pump displacement and work Boyle's Law for semi-adiabatic compression. Do the math and work your way to a trial motor/pulley combination. Get an engineer or a hydraulic and air guy to help you. Compressor pumps have been made for centuries meaning all their characteritics have been reduced to tables somewhere.

Look here: http://www.google.com/search?hl=en&source=hp&ie=ISO-8859-1&q=HP+to+compress+air&btnG=Google+Search

Once you have that, sizing the motor and drive pulley are duck soup. Always work technical problems with actual numbers based in the real world. Any other way and you're stabbing in the dark.

cuemaker
04-07-2010, 07:57 PM
I have tried to find out more details about the pump, but Worthington wants $50 to dig up any info.....

I am currently running the motor on 220v... I posted where I couldnt do any pics...

Here is the current motor plate..
http://i201.photobucket.com/albums/aa129/xringx/aircompressor018.jpg

And the head....
http://i201.photobucket.com/albums/aa129/xringx/DSCN2176.jpg

And the plate on the cylinder head..
http://i201.photobucket.com/albums/aa129/xringx/aircompressor003.jpg

cuemaker
04-09-2010, 09:43 AM
I need assistance... In my last post, i have a pic of the plate off the pump of the compressor... I cant see photobucket pics at work, and need the info off the plate... can somebody post the info on it?

Thanks

drof34
04-09-2010, 02:04 PM
serial #; CVS 227

size ; 4-3/8/ 2-1/2 X1-5/8

model ; 5C - 2S