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What's the max sustained HP you can get from an induction motor on 120V?

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There are some missing factors in your question.
a)What is the rated HP of the motor?
b)What is the efficiency factor?
c)Single or Three Phase?
d)Cycles?
e)What are you using it for?
This should be found on a little data plate on the motor.
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Crossing boundaries here, unless you assume a perfect transfer of energy. Electrical power is voltage x current. You should be able to find the max current rating on the motor itself. This power is in watts, and 100kW = 138.1 hp.
This will be close for you. Other energy losses will be to heat and friction. If the motor is an expensive one, they may even specify the efficiency of the unit, which you could use to get a more accurate estimate.
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Oh, one thing I noticed is wrong. Max power does not occur at max efficiency. You'll be better off reading max HP off the plate on the motor.
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Backstory :: Mrs. and I were watching an re-run of Everybody Loves Raymond and he's purchased a vacuum that he claims is 4HP. I told Mrs. PH that I thought 4HP wasn't possible with 120V household current.

True or False?
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Yes!
The Cr*ftsman shop vac in my workshop at home is a 6HP, and plugs right into a regular outlet.
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It will all be based on the current you can get from your supply. 4HP is nearly 3000W, which, at 120V (which you don't get out your outlet), you'd need 25 amps. Only stoves, dryers and other large appliances get that much, and they're on their own breaker. All other circuits are either 10A or 15A.
It's possible, but not likely with "traditional" wiring.
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Yes!
The Cr*ftsman shop vac in my workshop at home is a 6HP, and plugs right into a regular outlet.
Hey, you're right! I guess it's time to pass my degrees back to the school....
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Hey, you're right!

Cuz I are a genius! Now the sooner new owners realize this, the sooner we can all be a big happy family again. :P


I guess it's time to pass my degrees back to the school....

It's all about application. When dealing with Vac units it's "Peak HP". Sort of a smoke and mirrors thing.. It may develop the Peak HP for a half second during starup and then drop down to a sustained HP that is quite a bit lower....and not apt to trip the breaker...or blow the fuse (for old farts like Andy and Gdawg). 8)
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Well I wear a double E, on my feet  , but I'm not sure about the HP. :P

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Hey, you're right!
Cuz I are a genius! Now the sooner new owners realize this, the sooner we can all be a big happy family again. :P Oh Wow, look it's a hot air balloon!! Nope, thats just Ranger's head
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There are some missing factors in your question.
a)What is the rated HP of the motor?
b)What is the efficiency factor?
c)Single or Three Phase?
d)Cycles?
e)What are you using it for?
This should be found on a little data plate on the motor.
I'm not electrical expert but I don't think they make three phase 120V motors....
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6880 posts
6 hp is roughly 4500 watts which would mean you need about 45 amps to run it. Now the starting load would be considerably more so you would probably need a 100 amp circuit to be able to use it. I never heard of any normal living room circuit of that capability. Most are 15 amps with some special ones at 20 amps.
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That's why I asked about sustained HP in my initial post.
I know manufacturers want to put up big HP numbers, so they use the max HP instead of sustained.
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That's why I asked about sustained HP in my initial post. I know manufacturers want to put up big HP numbers, so they use the max HP instead of sustained. Well, you could sustain the peak hp over a long period of time if the application of the motor required it. But doing that can cause bad things. That's where the duty cycle comes into play. Ideally, you can hit max load on a motor for it's duty cycle before you have to shut it down...or it'll break. Badly. And thanks to a couple of Google searches, I now understand all this. I forgot all about that torque thing....I guess I do get to keep my EE papers!

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