Knowledge You Can Build On — Est. 1998
Motor upgrade
Bob Moffett
>I am rebuilding an old Delta Band Saw for cutting turning blanks. I am able to get a Twianese 1 1/2 hp. motor for it, but it draws 20 amps on 110 or 10 amps on 220. I have a Delta contractor saw with a 1 1/2 hp motor and it only draws 11.5 amps on 115. Why does a Twianese motor draw so many amps for the same horsepower? Also, are they comparable quality motors?
Motor HP information! *LINK*
Steve Mushinski
>Bob,
The numbers do not add up at all. Without seeing the motors and the name plates it is very hard to say. I have added a link with some information about calculating HP's. It will show you that it isn't just simple math, as power factor and efficiency come into play. I hope it helps.
http://http://www.elec-toolbox.com/Formulas/Useful/formulas.htm
Re: Motor HP information!
Barry Irby
>My Delta 14" band saw came with a motor labeled 3/4 hp and it draws 11.6 amps at 120 volts and runs a the lower speed 1750 (?). It's OK, but more horses would be better.
Re: Motor upgrade
Wood Spinner
>Amps x volts divided by 743 = HP
They can play with the way it is done but this is the true fact of run hp.
Re: Motor upgrade
Bill Howatt
>If you want to get picky it is 746W/HP. However, the current rating on the nameplate can't be used directly in the calculation since the power-factor has to be known. The plate rating is the current the motor will draw for wire size and breaker specification. Only the real component of the power generates useful work. Then there is the matter of efficiency as well.
Bill
