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.
<[email protected]> wrote in message
news:d7fc718a-b4c7-4029-b6b7-4009c81bb047@x35g2000hsb.googlegroups.com...
>>
>> Before adding special circuits I would first plug it in to what you have
>> and
>> try it out during actual use.
>
> That's definitely what I'm doing, and I built the base for it and got
> it setup. Seems to run fine. The one set of 4 ft lights on the same
> circuit barely flicker when it starts up. It starts up fine with the
> spindle sander next to it running too, but that's just rated at 2.5
> amps. Still, if the manual is to be believed that should have brought
> upon the end of the world. The dehumidifier is also on that circuit,
> but we're getting to the end of the season where it's needed. Before
> you know it I will be freezing my ass off in there again.
>
>> On a 15 amp circuit I run a radio, lighting, 12 amp dust collector and a
>> 15
>> amp router, no problem at all unless the compressor comes on.
Might I also add that there isa 20" fan blowing on my circuit also.
> I can say that a TS and a space heater on a 20 amp circuit is a no
> go :) Well, it's a go.. to the panel to reset the breaker.
A space heater tends to use a constant higher amp so they will tend to use
most of the amps that they are rated at.. Electric motors tend to use more
amps getting up to speed than they do during actual usage.
On Sep 11, 1:29=A0pm, Chris Friesen <[email protected]> wrote:
> Robatoy wrote:
> > 756 watts per HP @ 100% efficiency. Most electrical motors run around
> > 90% or so.
>
> I think that's a bit optimistic. =A0Baldor's "premium efficiency" 3HP
> motor gives 85% efficiency and 96% power factor.
>
> Their more typical 3HP motor gives 78% efficiency and 85% power factor
> for a total efficiency of around 66%.
>
> Chris
I allocated 1000 watts for 1 HP. Close enough for giggles.
Hell, I have 6.5 HP vacuum which draws 10A!! How is THAT for
efficiency, eh? <G>
On Sep 11, 1:06 pm, Chris Friesen <[email protected]> wrote:
> [email protected] 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.
>
> Horsepower ratings aren't always all that precise, and motor efficiency
> can lead to higher max draw.
But marketing departments making specs sound as good as they can is
right up there with death and taxes. The Sawstop contractor saw
actually says 1-3/4 HP which I've never seen anything say.
> I suspect it's simply an inefficient motor.
I found this link which says the minimum efficiency for a NEMA "Design
B" should be 79%. I don't know what a Design B is.
http://www.engineeringtoolbox.com/electrical-motor-efficiency-d_655.html
Even at 75%, 20A at 115V is well over 2 HP. Or going the other way,
1.5 HP at 75% is 13A, which is exactly what my table saw says.
> Also, it's likely that the
> motor will hardly ever actually draw the rated amount. Most shop tools
> (except for dust collectors) aren't running anywhere near full load.
The manual actually has a page where it says the machine will draw 10A
on 220V under normal use. Which doesn't make any sense, but that's
what it says.
On Sep 11, 12:45=A0pm, [email protected] wrote:
> My new edge sander was delivered today, Grizzly 6x80. =A0In the version
> of the manual on the website they list it as 1.5 HP 16A/8A. =A0But 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. =A0I just think it's very weird because if it's really drawing
> 20A then why are they calling it 1.5 HP? =A020A should give 2 HP. =A0I wa=
s
> under the impression that they couldn't lie about the amps, but HP
> ratings were more fudge-able. =A0It'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. =A0So 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. =A0I 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
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.)
On Thu, 11 Sep 2008 22:22:27 GMT, "stu" <[email protected]> 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
Robatoy wrote:
> 756 watts per HP @ 100% efficiency. Most electrical motors run around
> 90% or so.
I think that's a bit optimistic. Baldor's "premium efficiency" 3HP
motor gives 85% efficiency and 96% power factor.
Their more typical 3HP motor gives 78% efficiency and 85% power factor
for a total efficiency of around 66%.
Chris
Not meaning to nit-pick but that is 746W=1HP
"Robatoy" <[email protected]> wrote in message
news:[email protected]...
On Sep 11, 12:45 pm, [email protected] 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
[email protected] 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.
Horsepower ratings aren't always all that precise, and motor efficiency
can lead to higher max draw.
I suspect it's simply an inefficient motor. Also, it's likely that the
motor will hardly ever actually draw the rated amount. Most shop tools
(except for dust collectors) aren't running anywhere near full load.
Chris
Watts=volts x amps. 1HP =746Watts. Double the voltage then half the amps. It
is 240 volts and 120volts in residential. 110volts and 220 volts went the
way of the Doh-doh bird long ago. Using old numbers with newer equipment
will do funny things to your mathematical calculations compared to real
world measurements.
Stu
"Leon" <[email protected]> wrote in message
news:[email protected]...
>
> <[email protected]> wrote in message
> news:2d9ae864-5192-4514-88ec-eaf511294120@k37g2000hsf.googlegroups.com...
>> 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.
>
>
> Before adding special circuits I would first plug it in to what you have
> and try it out during actual use.
>
> On a 15 amp circuit I run a radio, lighting, 12 amp dust collector and a
> 15 amp router, no problem at all unless the compressor comes on.
> typically your heaviest amp draw is going to be when you start the
> machine, usually you don't work on the machine until it comes up to speed
> and the amp demand goes down.
>
<[email protected]> wrote in message
news:2d9ae864-5192-4514-88ec-eaf511294120@k37g2000hsf.googlegroups.com...
> 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.
Before adding special circuits I would first plug it in to what you have and
try it out during actual use.
On a 15 amp circuit I run a radio, lighting, 12 amp dust collector and a 15
amp router, no problem at all unless the compressor comes on. typically
your heaviest amp draw is going to be when you start the machine, usually
you don't work on the machine until it comes up to speed and the amp demand
goes down.
[email protected] wrote:
> Anyway, I raised the topic not so much in regards to what I need to do
> to make it work, I can deal with that. It was more that I have
> definitely heard on the wreck that you can't trust the hp rating, but
> the amps were more reliable because that gets tested by UL.
UL tests that the amps don't ever go higher than the nameplate. They
don't test whether they go as high as the nameplate.
I've heard a few stories of drill/jigsaw/etc manufacturers padding the
amperage rating to make the tool seem more powerful. No evidence that
it actually happened, but it sounds like something someone would do...
Chris
On Sep 11, 4:24 pm, "Leon" <[email protected]> wrote:
> <[email protected]> wrote in message
>
> news:2d9ae864-5192-4514-88ec-eaf511294120@k37g2000hsf.googlegroups.com...
>
>
>
> > 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.
>
> Before adding special circuits I would first plug it in to what you have and
> try it out during actual use.
That's definitely what I'm doing, and I built the base for it and got
it setup. Seems to run fine. The one set of 4 ft lights on the same
circuit barely flicker when it starts up. It starts up fine with the
spindle sander next to it running too, but that's just rated at 2.5
amps. Still, if the manual is to be believed that should have brought
upon the end of the world. The dehumidifier is also on that circuit,
but we're getting to the end of the season where it's needed. Before
you know it I will be freezing my ass off in there again.
> On a 15 amp circuit I run a radio, lighting, 12 amp dust collector and a 15
> amp router, no problem at all unless the compressor comes on.
I can say that a TS and a space heater on a 20 amp circuit is a no
go :) Well, it's a go.. to the panel to reset the breaker.
Anyway, I raised the topic not so much in regards to what I need to do
to make it work, I can deal with that. It was more that I have
definitely heard on the wreck that you can't trust the hp rating, but
the amps were more reliable because that gets tested by UL. And I
just wonder if the marketing departments haven't figured that out and
now you can't trust anything.
Maybe they stamped the motor with a ball-park reading, with a clamp on
ampmeter it will only draw 8A when on full load... I like grizzly tools,
they've been good to me. Lots of luck
<[email protected]> wrote in message
news:2d9ae864-5192-4514-88ec-eaf511294120@k37g2000hsf.googlegroups.com...
> 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.