HP ?
- Thread starter shaw0486
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It comes from physics which compares electrical energy in watts to mechanical energy measured in HP. Among other things both can converted 100% to heat, and the two amounts of heat can be directly compared.
Tapatalk!
Tapatalk!
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Don't fall into the common action of comparing electrical input electrical watts versus mechanical output horsepower.
For example, with motors, not only are you changing units of measurement you are changing where the reference point where the measurements are being made.
When comparing the difference between input watts and output horsepower, you need to consider efficiency.
Also assuming you mean = not +
It is quite simply the conversion between Imperial units to SI (metric) units.
1 HP = 550 ft-lbf/sec
Units of force times distance per unit of time.
(lbf is pounds force not lb mass)
It's the same for SI.
The unit of power is the Watt.
It also can be expressed as units of force times distance per unit of time
1 W = 1Nm/s
One Newton times one metre in one second.
Newton being force, metre distance and second being time.
All you then need are the conversion factors.
One pound force is about 4.45 Newtons.
One foot is 0.305 metres.
And one second is.......well one second.
So you get 1 HP = =550*4.45*0.305 W
Rounding gets you 746 W
The important thing to remember is that power is power.
It may be used to quantify mechanical output or electrical input but it is still power. Just power. Whatever units you use.
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