BIG PMDC servo motor

[Kilted]

Found on eBay this permanent magnet motor is bigger than any I have ever seen.  If this does not work as a Mill you can stick some batteries with it and drive it to work!!  It could easily be used with a 120VDC pack and could drive a small car with a range of about 20-40 miles.  Below is a copy of the eBay listing.

What size rotor would it take to turn this monster?  It seems like it is to big, I was looking at the Otherpower eBay guides to wind power and the largest rotor listed is 20' in 26mph wind produces 9640watts.  That is 'only' about 13hp this motor is well beyond that.  It also has a built in tach so you will always know the shaft rpm.

With rated out at 1200rpm would a gearup still be required to get full output?  I know little about wind turbines but I have figured out the larger the rotor the slower it turns.  

This appears to be a Peerless DC Servo motor model 2190

http://peerlesselectric.com/servo.htm

--  Brandy

Ebay listing:

http://cgi.ebay.com/4900W-DC-WIND-GENERATOR-7-HP-ELECTRIC-VEHICLE-MOTOR_W0QQitemZ330183868487QQihZ01



4QQcategoryZ67008QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

PRODUCE OVER 21,400 WATTS OF POWER.

VISIT OUR STORE; WE SELL AC/DC ELECTRIC MOTORS, WIND GENERATORS AND MUCH MORE WITH HIGH QUALITY AND GREAT PRICES. DON'T FORGET TO ADD US TO YOUR FAVORITE LIST. THANKS FOR YOUR INTEREST!!!!

4900W GENERATOR DC 7 HP ELECTRIC VEHICLE MOTOR/ SERIOUS HOME WIND POWER

This is massive and powerful motor/generator. Ideal for robotic, lathe spindle, servo systems requiring extreme high torque ect (comes with integral tach generator which produces 19V per 1,000 RPM). This is the ideal wind power generator for the home. It will provide more than enough electric power for the home, over 4900 watts. It will produce 12V at approximately 70 RPM . This is with no gears. This makes it exceptionally well suited for wind power generation. Wth only moderate winds (a breeze you might not even notice) you can produce the energy you need. Massive Bearings and a large shaft makes direct drive easy as a motor or generator. Why pay an electric bill when you can sell it back to your electricity provider (in many places here in the US this is what done by many people who have successfully utilized wind power and this is exactly the motor/generator that can provide that). Even in a relatively modest wind, you will be able to provide full output from this Motor/generator. As a motor gain over 7 HP at 230V DC and approximately 1200RPM. This motor will start running with as little 1.2 Volts DC approximately  and is rated to 230 Volts DC. Elevate the voltage to 120 volts and gain over 3.5 HP. This motor/Generator is manufactured by PEERLESS and has stated on the nameplate a rating of current of over 90 Armature AMPS at 230V DC and 1200 RPM. This motor produces too much torque to fully test it at that current rating. This is why it is rated at only 7 HP and not 30 HP. At over 90 amps it will produce over 135 foot  pound of torque. Its torque constant was measured at 1.5 foot pound AMP (1.5 x 90 = 135). This Motor/Generator looks weathered from improper storage. It has some rust and scuffs on it. I can't validate its functioning at over 90Amps and so It is rate as 7 HP only. The two large power leads would suggest it can handle this amount of current continuously. However I can only speak for how much it was tested for. This also makes a good Vehicle motor because its low rpm would mean easy gearing or no gears at all. Direct drive.  The pictures are for illustration purposes of the generator you will receive.

SPECIFICATIONS:

7 HP

VOLTAGE 230 DC

AMPS 93.3 MAX. ARMATURE PULSE (NAMEPLATE AMPS)

RPM 1200

ROTATION REVERSIBLE

ENCLOSURE TENV

DUTY CONTINUOUS

MOUNT 4 BOLT 9" DIAGONAL

SHAFT 1 3/8" DIAM. X 2" WITH KEYWAY

SIZE 18 7/8" X 7 1/2" X 9 1/2"

SHPG. 97 LBS (ESTIMATED)

[2windy]

This motor was sold at Surplus Center for $99.00 for a long time, til stock ran out. They had quite alot of them. Someone must of thought it was a good deal and bought them all.

[Kilted]

Thank you, I did not know that.  In talking this motor over with a friend at work.  We came to a couple conclusions.  The motor voltage and current ratings are just where mechanical engineers start from, the delta temperature rise is more important. The max amp comment "Armature Pulse" this sounds like a short like a few minutes not the continuous rating.  The cont rating is likely to be in the 10hp range 7500 - 8000 watts.  Still an impressive amount of power, if you have the right conditions. That motor sold I wonder if the person who bought it, bought a motor or generator.  It's large enough to due either job.  

Even at $99 I still would not have bought it just to big, for me to handle.  I'm beginning to see the problem of finding a motor/generator with the right weight, output at the desired rpm.  I slowly coming to understand why this group roll-your-own.

For those still wondering most DC conversion from Infernal Combustion Engine to all electric, use shut wound motors like http://www.adcmotors.com/ or http://www.go-ev.com/motors-warp.html.  A very interesting SUV came in via email today http://www.badboybuggieshillcountry.com and http://www.badboybuggieshillcountry.com.

--  Brandy

[elvin1949]

Brandy

 My brother-in-law bought one of those badboy,s.

He liked it so well he GAVE away his honda 4-wheeler.

later

Elvin