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You ever get amused by some tools claiming horsepower ratings that are seemingly impossible from a 15 AMP, 120 volt supply ?

Jeremy here decided to test a 4.5 HP ShopVac.
And by the way the package clearly says "output", although they do claim it as a "peak" rating.

Hope I am not spoiling it for you, but Jeremy couldn't get 4.5 HP from that motor.

At rated voltage and current, it produced .87 HP.
However, by loading it heavily, he did manage to get 1.68 HP very briefly before smoking the motor.

 

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One horsepower in electrical power (here, input to the vacuum cleaner) is approximately 750 watts. I think the actual number is 746 but I don't know where that came from.

There is a concept referred to as instantaneous peak power which I suppose for a vacuum cleaner is ability to produce a certain amount of suction for, say, a quarter of a second. That would be meaningless and useless to the consumer/user.

Some fifty years ago home entertainment companies advertised stereo systems with stupendous amounts of audio power. Consumer Reports magazine tested one console stereo advertised to have 300 watts of output and measured two watts audio output per channel using standards close to what we used today.
 

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One horsepower in electrical power (here, input to the vacuum cleaner) is approximately 750 watts. I think the actual number is 746 but I don't know where that came from.

That figure is misleading. It doesn't take into account for any losses, and no motor is 100% efficient.
 

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If 1 HP is 750 watts then 4.5 HP = 3375 watts which is equal to 28.125 amps. Try to get that much current out of a 120V outlet.
I=P/V
 

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SPS.......Thanks......I think we all know much of advertising is B/S or miss-leading at best.....but it's fun to see some exposed.

(Sometimes I wish I was flush independently wealthy and could support national advertising exposing/explaining some ,or many, of these "scams".

I wouldn't know where to start, maybe Home Advisor who I know how they work or maybe HomeLight which I believe/think probably is the same advertising model. Don't know personally....is it just a referral system based on parties who pay for their referral....anybody know. ???)
 

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Jeremy here decided to test a 4.5 HP ShopVac.
And by the way the package clearly says "output", although they do claim it as a "peak" rating.

At rated voltage and current, it produced .87 HP.
The rating was 9.9A @ 120V. If you look at any NEC or CEC motor table that will tell you it is ~ 1/2HP motor. I doubt in use it would be close to that, until the hose gets clogged ! So more likely a 1/4HP motor.
Peak HP is a mfr garbage hype lol

Someone mentioned compressors. Similar 'over exaggerating' the HP, but at least it was still on the motor curve. Not that it would last very long at that load, but it could output it for 30 mins or so.


Lawnmowers hype the HP too
Nissan did it too, so did Ford and VW in their cars and trucks :surprise:

I can post the HP charts (CEC) if anyone is interested.
 

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A lot of homeowner stuff is an optimistic peak horsepower just before stall number. Commercial stuff is usually continuous running horsepower.
 
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