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Eng sys to power a machine 7 ft lbs of torque for 900 rpm (constant load need) 24volt dc mtr have specs w/ gear red 2-1? Answered

Crushing grain etc, have the model number for the motor, need solar power to run 62.5 full load amps.  - have more info if needed

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steveastroukBest Answer (author)2012-06-06

Sam,

Yes, I'd always suggest a battery bank between the panels and the load, and yes, there would HAVE to be a shut off.

You MIGHT also consider using reflectors to increase the insolation on the panel - the cells will give more power out, without increasing the area/cost.

Steve

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steveastrouk (author)2012-06-05

We don't charge for extra words.

I reckon that's 900W.

What's the question ?

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frollard (author)steveastrouk2012-06-05

regardless of gear reduction, 24v @ 62 amps would be excess of 1600W at the motor shaft would it not? (Agreed, not a lot to go on for the question)

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Jack A Lopez (author)frollard2012-06-05

The mechanical power works out to about 900 W. That's just 7ft*lb multiplied by 900 rev/min. I mean after converting all the units:
(7.0*1.355818)*(900/60)*2*pi = (9.4907 N*m)*(94.248 rad/s) = 894.48

So this thingy seems to be kinda high powered, for a solar-powered thingy.

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user

That's what I did too.

The question is, what's the question.....

Steve

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samhall (author)steveastrouk2012-06-06

We have a Grain, coffee, seed crushing machine, it needs to be running 900 RPM's to process the material to the correct micron size, we are taking it over seas to West Africa so we need to convert to a DC motor and run it with solar, I have a quote for a motor that I think will do the work but we are not up to speed on the solar panel's we will be needing.

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steveastrouk (author)samhall2012-06-06

RIGHT !

Now you're talking !

So, the naiive figure is 900W of panel, that, however is a figure derived from noon normal sun - sun at its highest, and brightest, and the panel orientated perpendicular to that. I think I'd want a high voltage low current panel and an inverter for an AC motor - you'll win on efficiency and reliability over a Shunt wound DC motor.

Shoot for at least 1500W of panel perhaps.

Steve

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steveastrouk (author)samhall2012-06-06

Also, battery backup will protect the motor from low panel voltages.

Don't forget to tick the best answer box too.....

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samhall (author)steveastrouk2012-06-06

Steve,
Doesn't the panel supply the battery and the battery supplies the motor and is there a shut off switch?

And thank you, you have been very helpful!
Sam

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user

An American converting to SI ???

:-O

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samhall (author)frollard2012-06-06

We have a Grain, coffee, seed crushing machine, it needs to be running 900 RPM's to process the material to the correct micron size, we are taking it over seas to West Africa so we need to convert to a DC motor and run it with solar, I have a quote for a motor that I think will do the work but we are not up to speed on the solar panel's we will be needing.

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steveastrouk (author)frollard2012-06-06

Exactly. So why is the load 900W ?

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samhall (author)2012-06-05

Oh, ok thanks. It's 900 RPM

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