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Which motor would be most powerful? The "6 hp" motor HF sells or the "5 hp heavy duty"?

Here's the link to the 5 hp heavy duty: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3094

Here's the 6 hp: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96403

Normally I would expect the 6 hp to be more powerful, but the loaded amp rating on the 6 hp is 16.08 amps while the 5 hp motor is "23-21".

I'm thinking about turning a smaller two stage compressor plus one of these with it: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93786

Heck, if it would be possible I would love to turn two of the HF single stage compressors with the motor.
 

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Did you see the RPM differences on the e-motors and what the A/C pump requires?

The 6hp is rated at ~3400 while the 5hp says max 1800...

The reversable option on the 6hp would be a nice plus too.
 

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Here's a REAL 5hp motor..
http://cgi.ebay.com/NEW-5-HP-BALDOR-AIRCOMPRESSOR-ELECTRIC-MOTOR-L1410T_W0QQitemZ160254215911QQihZ006QQcategoryZ26226QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I've got that one, works very well.

That HF compressor might require a REAL 3hp motor. A REAL 5hp motor might be able to run two of those compressors @ 110 ~ 120 psi (140 psi single stage is pushing it anyways..).

FYI, that's a 36 cubic inch compressor unit.
80mm bore 60mm stroke * 2 cylinders = 600cc's

Sheesh, the eaton compressors are WAY smaller than that (they advertise their $150 compressor head as a 13 cubic inch compressor).:confused:
 

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I've said it before, and I'll say it again...

That HF compressor takes a real 5 hp motor to turn it (if you are turning it at it's full rated speed).

I'm turning mine with a 5 hp 3450 rpm motor, 19.5 amps. I'm using a 2 groove 5 inch drive pulley and 2 "B" belts.

With a 3 hp, 14.5 amp motor, the speed fluctuates right on the edge of the centrifugal switch cutoff speed. You hear the switch constantly clicking on and off. This will kill the motor in short order.

The formula for figuring the hp of an electric motor is...

voltage x amps x efficiency x power factor / 746
 

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I'm running the 5 hp motor. (It's made by Marathon Electric and IS reversible by the way).
It's turning a large Quincy 2 stage head and running into a home size propane tank.
I've been running this setup hard for 8 years now and never had any problems.
It's a damn good motor IMO.
 

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I'm running the 5 hp motor. (It's made by Marathon Electric and IS reversible by the way).
It's turning a large Quincy 2 stage head and running into a home size propane tank.
I've been running this setup hard for 8 years now and never had any problems.
It's a damn good motor IMO.
FWIW 8yrs is a long time to assume they are the identical unit you have ;)

-Todd
 

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It's the same one they are still selling at my local HF.
I see them there at least every couple of weeks...same model number on the motor, same one in his link...same one.
 
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