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Generators & Electric Motors General Discussion

AC vs DC Power


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  #1  
Old 12-02-2018, 12:11:34 AM
opus opus is offline
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Default AC vs DC Power

Hypothetically; if I have a 5 hp engine and it will power an AC 120v generator that will give me say 13A.

Now if I take that same setup but with a DC powered 12v generator, will it take less hp to deliver 13A DC?

Boy, I hope that makes sense.

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Old 12-02-2018, 12:25:45 AM
AngolaGravely AngolaGravely is offline
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Default Re: AC vs DC

Quote:
Originally Posted by opus View Post
Hypothetically; if I have a 5 hp engine and it will power an AC 120v generator that will give me say 13A.

Now if I take that same setup but with a DC powered 12v generator, will it take less hp to deliver 13A DC?

Boy, I hope that makes sense.

12V @ 13A is 156 watts.

120V @ 13A is 1560 Watts.

A horsepower is roughly 744 watts.
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Old 12-02-2018, 01:58:39 AM
Thaumaturge Thaumaturge is online now
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Default Re: AC vs DC

Don't know if info will help much, but typical 12VDC "charger" outputs are powered off a separate, rectified aux winding. The current of such aux coils is limited by wire size of coils, rectifier size and circuit fuse or breaker.
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Old 12-02-2018, 10:32:22 AM
G.M.Johnson G.M.Johnson is offline
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Default Re: AC vs DC

12vdc @ 13 amps you can get away with a lot less horsepower. A 1 hp motor will work just fine, but to give a little head room I would go with 1-1/2 hp. General rule of thumb is .75kw per HP.
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Old 12-02-2018, 11:25:28 AM
opus opus is offline
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Default Re: AC vs DC

This is all hypothetical, just going through things in my head.
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Old 12-03-2018, 01:41:59 AM
armandh armandh is offline
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Default Re: AC vs DC

volts x amps = watts which translates to horse power
same as ac it is power that counts
that is why one counts Root Mean Square volts

delivering 13 amps at 12 volts takes 1/10 the horsepower of 13 amps at 120 volts
"if the math all checks" who got the kudos for being first
not Marconi, rather Tesla, because he did the math
https://www.youtube.com/watch?v=y7VQ...=RDy7VQFfusQJk
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