HP/Amps
 

On Sep 11, 12:45*pm, wrote:
My new edge sander was delivered today, Grizzly 6x80. *In the version
of the manual on the website they list it as 1.5 HP 16A/8A. *But in
the manual that came with it and on the nameplate on the motor it says
1.5 HP 20A/10A.

Now I should probably run a dedicated 220V line to it regardless, but
for the time being I thought I was going to be fine on my 20A 110V
circuit. *I just think it's very weird because if it's really drawing
20A then why are they calling it 1.5 HP? *20A should give 2 HP. *I was
under the impression that they couldn't lie about the amps, but HP
ratings were more fudge-able. *It's a 1725 RPM motor, and looking at
the motors Grizzly has in their catalog the 1.5 HP 1725RPM model draws
17A, whereas the 3450RPM draws 15.6. *So I suppose that can explain a
bit of why the number is higher than I expect, but not all of it.
Have they just found a new source of really inefficient motors?

I wired it for 110 and it ran fine with no belt on it, but that
doesn't really mean anything. *I need to build a stand for it and get
it up on that before I start bolting on all the tables and whatnot so
it's going to be a while before I can test it under load.

756 watts per HP @ 100% efficiency. Most electrical motors run around
90% or so. Sooooo let's call it 1000 watfs per HP 12.5 amps at 120 V
will get you your horse-and-a-half. 6.25 amps at 240 V

HP/Amps
 

On Thu, 11 Sep 2008 22:22:27 GMT, "stu" wrote:

Sooooo let's call it 1000 watfs per HP 12.5 amps at 120 V
will get you your horse-and-a-half. 6.25 amps at 240 V

That should be fairly close to typical. The 3HP motor in my cabinet
saw claims to pull 14 amps at 240v

Tom Veatch
Wichita, KS
USA

HP/Amps
 

er... isn't the starting current somewhat higher than the running current -
(Back EMF and such?)


What's your fuse rating? If it's a slo-blo spec that would usually indicate
that a startup surge is expected and it will draw considerably more juice at
switch-on than when performing. In this case you can't relate ampage to
horses.

Is this what we're talking abiut, or have I missed the point?
(Sorry, I'm not really familiar with 110 v stuff 'cos we don't have it here
in domestics.)