Author Topic: Will this motor work as a generator ?  (Read 22054 times)

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wooferhound

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Will this motor work as a generator ?
« on: June 07, 2010, 08:58:15 AM »
OK ,  here is the math, it's not tough and will let you find good electric producing motors without too much problem

Lets say you are looking at a motor rated 2600 RPM at 24 volts
Now divide the RPM by the voltage, 2600 / 24 = 108.33
you will need 108.33 RPM to make 1 volt
Now multiply the 'RPM per volt' times your planned Cut-In voltage
108.33 RPM times 12 volt Cut-In voltage equals 1300 RPM

There you go, your motor will make 12 volts when it reaches 1300 RPM
A proper Flooded Lead Acid battery is not really fully charged until it reaches 14.6 volts.
108.33 RPM times 14.6 volt Full-Charge voltage equals 1582 RPM
Too doggone fast.

That should be enough to figure out for yourself which one is a good generator.

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www.am27

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Re: Will this motor work as a generator ?
« Reply #1 on: July 09, 2012, 03:21:57 AM »
Wow you described it in such a simple way. Thank you.

txtinner

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Re: Will this motor work as a generator ?
« Reply #2 on: December 11, 2012, 06:10:49 AM »
You guys must be reading my mind, and thanks wooferhound
For the reply to this question.
I am currently reading a book on Wind Generators, and thinking of building my first with a car alternator, or if I can find an old VW generator.
I'm still in the building stage of my workshop, but will soon have it inclosed and in the dry. Then will come the building wiring, and the fun part begins.
I have been looking into the Duel Core Alternator built by Missouri Wind and Solar as a backup power source, which will also give me 3 Phase to run machinery.
Any suggestions are deeply appreciated.

spottrouble

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Re: Will this motor work as a generator ?
« Reply #3 on: December 11, 2012, 12:31:38 PM »
You might want to do a search for MSW on here, in a nutshell, don't walk away, RUN!

Frank S

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Re: Will this motor work as a generator ?
« Reply #4 on: December 11, 2012, 01:21:18 PM »
You guys must be reading my mind, and thanks wooferhound
For the reply to this question.
I am currently reading a book on Wind Generators, and thinking of building my first with a car alternator, or if I can find an old VW generator.
I'm still in the building stage of my workshop, but will soon have it inclosed and in the dry. Then will come the building wiring, and the fun part begins.
I have been looking into the Duel Core Alternator built by Missouri Wind and Solar as a backup power source, which will also give me 3 Phase to run machinery.
Any suggestions are deeply appreciated.

I think you will find that getting stable 220 3 phase to run equipment is going to take a commercial sized machine and sophisticated controls Its doable but not for the faint at heart or shallow pockets.
 nothing that MSW has will even come close.
  I've looked at the designs of over 1000 wind turbines for a suitable affordable unit to power up to 20 KW installed 3ph equipment. I've even been working on designing one the size that I was thinking I need. What it boils down to if I can keep the use requirement under 5 KW and could depend on good wind then the largest Bergy with an over-sized turbine  on a 900 ft tower is about the minimum that would fit the bill.
 Getting voltage to charge a large bank of batteries then using a PSW inverter  to  give you 220 & split phase is a lot different than running 3 ph  You can get 3 ph from a bank it just means you step up to the cash register
I live so far outside of the box, when I die they will stretch my carcass over the coffin

bart

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Re: Will this motor work as a generator ?
« Reply #5 on: December 11, 2012, 03:10:33 PM »
   Have no idea how large a motor you all are talking about using, but am currently running a 3 phase  1 1/2 hp blower motor off of a vfd drive fed from 240 split phase. You de-rate the drive by 1/2. Have also 2-20 hp vfd's that have also been used successfully, mainly on pumps.
  As a side note, have not tried running off of the Magnum inverter yet, but plan on giving it a test run.

birdhouse

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Re: Will this motor work as a generator ?
« Reply #6 on: December 11, 2012, 11:08:30 PM »
i'm using a 3 phase fanuc motor rectified to single phase DC.  ratings are 2000rpm, 140V and 20A into a 24VDC battery bank. (60lb motor) it'll max at 1000w, but usually 300-600w with a 8.5' three blader...  design of tsr-6.5

adam

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Re: Will this motor work as a generator ?
« Reply #7 on: April 26, 2013, 06:59:24 AM »
The portable generators on the market run at 3000 rpm for 50hz and 3600 rpm for 60hz.

If you can use a gear system to get this speed it would be worth considering a "spares and repairs" generator from eBay etc, with an engine that isn't running. The only catch is you cannot test the alternator without the engine running. (To buy a new alternator costs LOTS!)