re:Re: more horsepower (defs)

Al Lenz,

I'm enjoying your humor!

Unfortunately the books don't say the standard is power in minus
losses equals power out. They say 746 Watts IS a horsepower.
Increased efficiency of modern electrics makes this definition
obsolete and even more arbitrary than it was originally...

Ballendo

P.S. The efficiency numbers you used in your earlier post were from
the electrical HP side. Compared to the Mechanical HP side. Not a
fair comparison, which is what I've been saying all along...


ballendo@y... wrote:

> How do those of you in the "Watts in = HP out" 'camp' account for
>the increased torque ratings of stepper motors through the use of
>better magnets?

Easy, better materials and advanced engineering = higher efficiency,
BUT still less tghan 100 percent:-)

Al

PS, It's not Watts in = HP out, but power in - losses = power out.
Or, since the time is the same for input and output, it follows
energy or work can be substituted in the definition of efficiency,
i.e. energy out / energy in, work out / work in, etc. As long as
the units are consistant, they may be expressed in whatever form
is convenient. Since electric motors convert electrical energy
to mechanical energy, watts and HP are common. I tend to prefer
stone-furlong / fortnight, but can't seem to get it to catch on<g>
al