I was talking with my dad the other day and he mentioned he might by a
3HP TS from a friend. It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4. I guess my question (apart from
the obviose of increaced cutting power) is what is the real
difference. I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw. Also, can
3HP really run on 110? He seems to think it can. I have not been
able to bog down my TS and I have always found cutting to be great.
The only thing I really cut though are Oak and Ply. What benifits
would I expect with an upgrade? Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

I'm guessing anything bigger is just more bragging rights, but what do
I know. Any insite appreciated!
Mark

"DejaVoodoo" wrote:

I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw.

Actually, higher voltage will allow more of the power you are buying
to be used by the motor.

Reason:

Less power is wasted heating up the wire delivering the power to the
motor (Ohms Law stuff)

Also, can
3HP really run on 110?

NO, not and get any work done.

Bottom Line........................

The higher the voltage, the better since it reduces line losses thus
more power to the tool motor.

Lew

"DejaVoodoo" wrote in message
...
I was talking with my dad the other day and he mentioned he might by a
3HP TS from a friend. It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4. I guess my question (apart from
the obviose of increaced cutting power) is what is the real
difference. I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw. Also, can
3HP really run on 110? He seems to think it can. I have not been
able to bog down my TS and I have always found cutting to be great.
The only thing I really cut though are Oak and Ply. What benifits
would I expect with an upgrade? Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?


A true 3hp will likely not run on 110 volts, you typically have to go with
220 for a true 3 hp. There are some motors that claim 3 hp even 6.5 hp out
of 110 volts but basically the only similirity is the energy it is consuming
for a split second before it stalls.
Typically however 220 motors will run with little voltage drop, usually when
running on 220 volts the motor will come up to speed almost instantly vs.
havig to wind up on 110 volt.

My 3hp Jet on 220 will resaw a 1x6 piece of Ipe with the blade fully
burrined all the way up with no indication of strain. Ipe is about 2.5
times harder than Oak.



For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

I'm guessing anything bigger is just more bragging rights, but what do
I know. Any insite appreciated!

Well no, there is a very noticable differnce in performance. You just dont
have a stall problem regardless of what wood you are cutting and how deep
the cut. Now if you go from a 3 hp to a 5 hp in a at home setting, that
would be bragging.

You are pretty much maxed out with your current saw, to improve performance
you would probably need to step up to a cabinet saw running on 220 volts.

On Sat, 6 Sep 2008 16:14:05 -0700 (PDT), DejaVoodoo
wrote:

I rewired my saw for 220 - but doubt that give me an HP
upgrade

It didn't. What it did was reduce the amperage required by the saw.
The advantage of that is as Lew said, less voltage drop in the wiring
making a little more power available at the saw. How much depends
entirely on the electrical resistance in the wiring to the saw.
Assuming the same wiring resistance, the percentage voltage drop for a
given wattage at 240v is 1/4 that at 120v.

Also, can 3HP really run on 110?

Theoretically, yes. You could run a 3HP motor on 1.5 volt flashlight
batteries - theoretically. But it's not practical, either the 1.5 or
120 volts. You need a minimum 20 amp circuit at 240 volts for most 3HP
machines. Double that for 120 volts although with a high efficiency
motor you might squeak by on a 30 amp circuit. But you wouldn't be
happy with the results. In fact, I doubt that you're going to find
very many 3HP woodworking machines that can be configured for 120 volt
operation.

Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

Again, theoretically yes. If you can find a higher HP motor with the
same NEMA or IEC frame size, it should be a fairly simple matter to
replace the motor. Otherwise, it probably wouldn't be worth the
trouble or expense to rebuild, modify, or fabricate new brackets to
hang the motor.

Although the saw structure should have been designed with a
considerable safety factor, it's impossible to say, in general, what
problems might arise from the increased loads if you do indeed use the
higher power available from the motor. Also you have to consider
getting the additional power from the motor to the blade. Most, if not
all, the 1 to 1.5 HP contractor saws use a single V-belt to spin the
blade. My 3 HP saw uses a 3 groove sheave and 3 V-belts. Overkill?
Maybe, but you might find that with a new, higher power motor, you
also need to upgrade the sheave/belt configuration.

For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

I can certainly understand why. The difference must be like night and
day.


I'm guessing anything bigger is just more bragging rights,

My personal opinion is that for hobbyist, home workshop applications,
anything much over about 3HP in a 10" saw is getting into the
"bragging rights" area. Occasionally, the extra power in a 5HP machine
will come in handy, and is very nice to have when you need it, but I
believe most hobbyist woodworkers rarely use the extra power. I can
say, for certain, that I've never had any problems with insufficient
power on my 3HP saw.

But, I have one of each, and I see the difference between a 1.5HP
contractor saw and a 3HP cabinet saw as being quite significant.
Possibly not to the framing carpenter working with HD "white wood",
but certainly to anyone doing much with furniture grade hardwoods.

Tom Veatch
Wichita, KS
USA

On Sep 6, 4:14*pm, DejaVoodoo wrote

:..... *What benifits
would I expect with an upgrade?

the biggest advantage is safety. an underpowered saw will bog down
sooner. bogging down is likely to be followed by kickback.
the next advantage is being able to cut thicker/harder stuff faster/
more smoothly.
the next advantage is being able to run blades with higher tooth
counts.


*Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

some saws have proprietary motors. you'll have to research yours.

DejaVoodoo wrote:

snipped

It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4.

I have not been
able to bog down my TS and I have always found cutting to be great.
The only thing I really cut though are Oak and Ply.

I'm guessing anything bigger is just more bragging rights, but what do
I know.

When you start ripping up lots of 3" hardwood you'll understand.

--

dadiOH
____________________________

dadiOH's dandies v3.06...
....a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico

"DejaVoodoo" wrote in message
...
I was talking with my dad the other day and he mentioned he might by a
3HP TS from a friend. It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4. I guess my question (apart from
the obviose of increaced cutting power) is what is the real
difference. I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw. Also, can
3HP really run on 110? He seems to think it can. I have not been
able to bog down my TS and I have always found cutting to be great.
The only thing I really cut though are Oak and Ply. What benifits
would I expect with an upgrade? Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

I'm guessing anything bigger is just more bragging rights, but what do
I know. Any insite appreciated!
Mark

I'd be wondering if that is a 3hp induction motor or a universal motor.

HUGE difference between the two. I laugh anytime I see a shop vac being sold
as a 7 1/2 hp machine. Then cry when someone believes it.

Mike

"Stuart" wrote in message
...
In article ,
Leon wrote:
A true 3hp will likely not run on 110 volts, you typically have to go
with 220 for a true 3 hp.

And here in the UK, where 240V is standard, we would consider 3hp as the
sensible limit. Anything more and we would be looking for 3ph.

Stuart

--
Stuart Winsor

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk
Alas, over here in the US, you have great difficulty getting 3 phase power.
My house was built in the late 1960s, and some on my block were built in the
early 1960s. The latter houses have 3 phase power for the A/C, but I don't.
This situation exists even though all of the transforms for my block reside
on a pole behind my house.
Three phase power might help me quite a bit as my A/C unit uses a 5 hp
compressor motor. The lights always flicker when that thing turns on.
Jim

On Sat, 6 Sep 2008 16:14:05 -0700 (PDT), DejaVoodoo
wrote:

I was talking with my dad the other day and he mentioned he might by a
3HP TS from a friend. It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4. I guess my question (apart from
the obviose of increaced cutting power) is what is the real
difference. I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw. Also, can
3HP really run on 110? He seems to think it can. I have not been
able to bog down my TS and I have always found cutting to be great.
The only thing I really cut though are Oak and Ply. What benifits
would I expect with an upgrade? Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

I'm guessing anything bigger is just more bragging rights, but what do
I know. Any insite appreciated!
Mark

Keep in mind that you may need 5 HP+ when a DC and air filters are
running. A motor can be replaced in a table saw--I'd suspect a belt
drive type is easier to swap. In my opinion, table saw power is less
important than a large flat cast-iron table, a quality precision
fence, and a sharp blade. If your 1.75 HP is not constantly bogging
down I doubt you need 3 HP.

"Stuart" wrote in message
...
In article ,
Leon wrote:
A true 3hp will likely not run on 110 volts, you typically have to go
with 220 for a true 3 hp.

And here in the UK, where 240V is standard, we would consider 3hp as the
sensible limit. Anything more and we would be looking for 3ph.


I was wondering, in the UK the standard voltage is 240V, what is the normal
gauge used for wiring in a home?

In article ,
Jim wrote:
Alas, over here in the US, you have great difficulty getting 3 phase
power.

No different over here actually. If you get a unit on an industrial
estate, or maybe a farm might have it, otherwise, even though it's running
down the road outside your house a few feet a way it costs "lots" to have
it installed.

Mind you, in the UK, because of the high cost of land, you'd be lucky to
have enough space anyway. Like yours, my house was built in the 60s and
all I have is a garage about 8ft x 16ft for my workshop [1]. A friend of
mine has a workshop just under 20ft x 20ft and I'm very envious. He could
have larger but if he did his local tax would go up.

Stuart

[1] See Google earth 52deg 20' 27.45"N : 1deg 34' 57.03"W. Don't be fooled
by the apparent size of the dwelling, its a typical british
"Semi-detached" house - two dwellings built side by side and sharing a
"party" wall. The conservatory belongs to my neighbour. I have a ground
floor area of around 600sq ft. My neighbours house is currently on the
market and the asking price is 280,000 pounds

--
Stuart Winsor

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk

In article ,
Leon wrote:

I was wondering, in the UK the standard voltage is 240V, what is the
normal gauge used for wiring in a home?

Which wiring? :-)

2.5mmsq twin and earth would be normal for a power ring main - probably
feeding one floor. 30/32A fuse or MCB in the consumer unit because all
portable appliances are connected by a plug containing a fuse (max 13A).

A kitchen would normally have a ring main of its own these days.

6mmsq would feed a cooker, again fused at 30/32A but lighting might be
1-1.5mmsq with a 5A fuse - again this would be per floor..

The feed to my garage from the house is 6mmsq, 32A MCB, and then that is
distributed round the garage using a ring main of 2.5mmsq. This I
installed myself, most might have nothing more than a feed for some
lighting and possibly a socket outlet for a battery charger.

Sorry I don't know how these sizes translates to AWG.

As you are probably aware air conditioning is rare in homes in the UK and,
by and large, gas is used for heating and usually for cooking too.
Electric heating is very expensive and oil, which would be used in areas
away from town would be intermediate in price.

If you are out in the country and can obtain a regular supply of wood,
woodburners are also common for heating but possibly using LPG for cooking.

Stuart

--
Stuart Winsor

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk

Stuart wrote:
In article ,
Leon wrote:


I was wondering, in the UK the standard voltage is 240V, what is the
normal gauge used for wiring in a home?


Which wiring? :-)

2.5mmsq twin and earth would be normal for a power ring main - probably
feeding one floor. 30/32A fuse or MCB in the consumer unit because all
portable appliances are connected by a plug containing a fuse (max 13A).

A kitchen would normally have a ring main of its own these days.

6mmsq would feed a cooker, again fused at 30/32A but lighting might be
1-1.5mmsq with a 5A fuse - again this would be per floor..

The feed to my garage from the house is 6mmsq, 32A MCB, and then that is
distributed round the garage using a ring main of 2.5mmsq. This I
installed myself, most might have nothing more than a feed for some
lighting and possibly a socket outlet for a battery charger.

Sorry I don't know how these sizes translates to AWG.

As you are probably aware air conditioning is rare in homes in the UK and,
by and large, gas is used for heating and usually for cooking too.
Electric heating is very expensive and oil, which would be used in areas
away from town would be intermediate in price.

If you are out in the country and can obtain a regular supply of wood,
woodburners are also common for heating but possibly using LPG for cooking.

Stuart


2.5 mmsq - between 14 and 12 gauge
1.5 mmsq - between 14 and 16 gauge
6 mmsq - between 9 and 10 gauge


--
Jack Novak
Buffalo, NY - USA

"Stuart" wrote in message
...
In article ,
Leon wrote:

I was wondering, in the UK the standard voltage is 240V, what is the
normal gauge used for wiring in a home?

Which wiring? :-)

2.5mmsq twin and earth would be normal for a power ring main - probably
feeding one floor. 30/32A fuse or MCB in the consumer unit because all
portable appliances are connected by a plug containing a fuse (max 13A).

A kitchen would normally have a ring main of its own these days.

6mmsq would feed a cooker, again fused at 30/32A but lighting might be
1-1.5mmsq with a 5A fuse - again this would be per floor..

The feed to my garage from the house is 6mmsq, 32A MCB, and then that is
distributed round the garage using a ring main of 2.5mmsq. This I
installed myself, most might have nothing more than a feed for some
lighting and possibly a socket outlet for a battery charger.

Sorry I don't know how these sizes translates to AWG.

As you are probably aware air conditioning is rare in homes in the UK and,
by and large, gas is used for heating and usually for cooking too.
Electric heating is very expensive and oil, which would be used in areas
away from town would be intermediate in price.

If you are out in the country and can obtain a regular supply of wood,
woodburners are also common for heating but possibly using LPG for
cooking.

Stuart

--
Stuart Winsor

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk
I don't know what size wire connects my circuit breaker box to the wires on
the pole. I can tell you that the box is full of 15 and 20 amp circuit
breakers, 30 and 40 amp breakers for the kitchen and drier, as well as 60
amp breakers for the A/C. I use gas for water heating.
Jim

"Stuart" wrote in message
...
In article ,
Leon wrote:

I was wondering, in the UK the standard voltage is 240V, what is the
normal gauge used for wiring in a home?

Which wiring? :-)

An ordinary wall outlet.


Snip


Thank you

"Nova" wrote in message
news:5dXwk.766$jE1.506@trnddc03...


2.5 mmsq - between 14 and 12 gauge
1.5 mmsq - between 14 and 16 gauge
6 mmsq - between 9 and 10 gauge



Oh! Thank you Nova, looks similar to in the US. I would have thought much
smaller gauge.

"Stuart" wrote:

My understanding is that in the US you have a 220V supply centre
tapped to
earth giving you 220V for heavy loads such as A/C and heating and
110V for
other appliances. Is this correct?

Your circuitry is correct, it is known as a "Three wire Edison"
circuit

The voltage rating these days is 120V/240V for distribution equipment
such as transformers.

The voltage rating these days is 115V/230V for utilization equipment
such as motors.

The difference is to allow for line losses.

Lew

Stuart wrote:
In article ,
Jim wrote:
I don't know what size wire connects my circuit breaker box to the wires
on the pole. I can tell you that the box is full of 15 and 20 amp
circuit breakers, 30 and 40 amp breakers for the kitchen and drier, as
well as 60 amp breakers for the A/C. I use gas for water heating.

The majority of power distribution, other than to farms and such, in the
UK is by underground cable and I don't have any idea what size that is
either but the first thing it is connected to in the house is the
electricity supply company fuse. In our case it is 60A but in more modern
installations might be 80A or in a large modern house as high as 100A.

Good job we don't have A/C :-)

My understanding is that in the US you have a 220V supply centre tapped to
earth giving you 220V for heavy loads such as A/C and heating and 110V for
other appliances. Is this correct?

Hmmm, probably should be on alt.electrical-engineering or some such :-)

Where I am its 23.55 and I'm thinking of going to bed. Catch up with you
guys' posts in the morning.

Stuart;

You are correct about 220VAC in the US. In the circuit breaker box each
adjacent breaker is attached to alternate sides of the service entrance.
i.e. 1)left 2)right 3)left 4)right and so on. The second line of
breakers are just the opposite. The occasional 3phase circuit is wired
in a similar fashion except there are 3 circuits involved. Home 3 phase
is very rare.

Dave Nagel

In article ,
says...

"Stuart" wrote in message
...
In article ,
Leon wrote:
A true 3hp will likely not run on 110 volts, you typically have to go
with 220 for a true 3 hp.

And here in the UK, where 240V is standard, we would consider 3hp as the
sensible limit. Anything more and we would be looking for 3ph.

Stuart

--
Stuart Winsor

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk
Alas, over here in the US, you have great difficulty getting 3 phase power.
My house was built in the late 1960s, and some on my block were built in the
early 1960s. The latter houses have 3 phase power for the A/C, but I don't.
This situation exists even though all of the transforms for my block reside
on a pole behind my house.
Three phase power might help me quite a bit as my A/C unit uses a 5 hp
compressor motor. The lights always flicker when that thing turns on.

My house has two heat pumps (2.5T and 3.5T, IIRC)[*]. No flicker.
;-)
[*] also allows two zones.

--
Keith

In article de26a03d-45ec-4a41-8158-
,
says...
I was talking with my dad the other day and he mentioned he might by a
3HP TS from a friend. It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4. I guess my question (apart from
the obviose of increaced cutting power) is what is the real
difference. I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw.

It doesn't "smooth out" the power but as others have mentioned, it
will give you somewhat more power (and keep the motor cooler)
because there is less drop in the wires (all assuming the same sized
wiring).

Also, can 3HP really run on 110?

It *can*, but likely won't. 1HP ~= 750W, assuming 100% efficiency.
A 120V 30A circuit might be able to supply a 3HP motor, but it would
be a waste of copper (#10 wire required). A 220V 20A circuit is
almost always simpler and cheaper, all around.

He seems to think it can. I have not been
able to bog down my TS and I have always found cutting to be great.

Don't worry. Be happy.

The only thing I really cut though are Oak and Ply. What benifits
would I expect with an upgrade? Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

It likely can be replaced, but since you're happy with the saw now
there is little chance the "upgrade" would be worth the expense.

For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

A bit of difference there! ;-)

I'm guessing anything bigger is just more bragging rights, but what do
I know. Any insite appreciated!

For most, I think you're right on the money.

--
Keith

In article ,
says...

"DejaVoodoo" wrote in message
...
I was talking with my dad the other day and he mentioned he might by a
3HP TS from a friend. It got me wondering what the HP was on my Jet
Supersaw and I found it was 1 3/4. I guess my question (apart from
the obviose of increaced cutting power) is what is the real
difference. I rewired my saw for 220 - but doubt that give me an HP
upgrade, I bet it just kind of smooths out the power draw. Also, can
3HP really run on 110? He seems to think it can. I have not been
able to bog down my TS and I have always found cutting to be great.
The only thing I really cut though are Oak and Ply. What benifits
would I expect with an upgrade? Can a TS motor be replaced to
increase HP, or do you just have to buy a new saw?

For those that do not know, the supersaw was kind of a hybrid cabinet/
contractor saw. Personally I love it, but the only other saw I have
owned/used was a benchtop Skil.

I'm guessing anything bigger is just more bragging rights, but what do
I know. Any insite appreciated!
Mark

I'd be wondering if that is a 3hp induction motor or a universal motor.

HUGE difference between the two. I laugh anytime I see a shop vac being sold
as a 7 1/2 hp machine. Then cry when someone believes it.

With a 16ga 120V line cord. ;-)

IME, if it's got a belt it's an induction motor, if not it's a
universal. If it's *NOISY* it's a universal motor.

--
Keith

krw wrote:

IME, if it's got a belt it's an induction motor, if not it's a
universal.

There are some exceptions to this; bench grinder, horizontal
mortising/boring machine, hollow chisel mortiser, dust collector...

If it's *NOISY* it's a universal motor.

This one is pretty much guaranteed. Wailing like a banshee means universal.

Chris

On Sun, 7 Sep 2008 10:03:15 -0500, "The Davenport's"
wrote:


I'd be wondering if that is a 3hp induction motor or a universal motor.

HUGE difference between the two. I laugh anytime I see a shop vac being sold
as a 7 1/2 hp machine. Then cry when someone believes it.

Mike



Not really. Power is still Amps X Voltage (with phase angle considered
for AC) regardless of whether it's a universal or induction motor.

The difference is in the marketing department of the manufacturer's
sales organization. They like to claim as much power as they can get
away with for their shop-vac. So, most of that hype comes from using
the amperage drawn by the motor with the rotor locked - the absolute
maximum the motor will draw. That amperage multiplied by the supply
voltage gives a pseudo wattage value that can be converted to
Horsepower at the rate of 746 watts per HP.

Now that's the power consumed (or in marketing terms, "Developed") by
the motor under conditions in which it is actually producing no power
at all. Mechanical Power = Torque X rotational velocity (with the
proper units). So with rotation = 0, Power = 0.

That marketing approach to power ratings seems to be most often found
in small universal motor applications, but I've also seen applications
using induction motors emblazoned with such things a "7 HP Developed"
and in much smaller lettering "3 HP Running".

But, it's all marketing hype, not something intrinsic to universal vs
induction motors.


Tom Veatch
Wichita, KS
USA

In article ,
Tom Veatch wrote:
That marketing approach to power ratings seems to be most often found
in small universal motor applications, but I've also seen applications
using induction motors emblazoned with such things a "7 HP Developed"
and in much smaller lettering "3 HP Running".

Sounds like the same approach used for cheap audio systems, especially the
ones you attach to computers. You know, the ones that say 200W and are fed
from a wall-wart the size of a matchbox.

--
Stuart Winsor

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk

Stuart wrote:
In article ,
Tom Veatch wrote:
That marketing approach to power ratings seems to be most often found
in small universal motor applications, but I've also seen applications
using induction motors emblazoned with such things a "7 HP Developed"
and in much smaller lettering "3 HP Running".

Sounds like the same approach used for cheap audio systems, especially the
ones you attach to computers. You know, the ones that say 200W and are fed
from a wall-wart the size of a matchbox.



And Monster Cable and K&N Air Filters.

All work miracles!

In article ,
says...
In article ,
Tom Veatch wrote:
That marketing approach to power ratings seems to be most often found
in small universal motor applications, but I've also seen applications
using induction motors emblazoned with such things a "7 HP Developed"
and in much smaller lettering "3 HP Running".

Sounds like the same approach used for cheap audio systems, especially the
ones you attach to computers. You know, the ones that say 200W and are fed
from a wall-wart the size of a matchbox.

Sorta, except the audiophools are even more creative. They take the
open circuit voltage times the short circuit current and give it a
technical term lie "music power". If they are really creative
they'll call it "RMS music power" or some other nonsensical term.
It would be like measuring the rotor torque close to stall times the
unloaded RPM.

--
Keith

krw wrote in
t:

In article ,
says...
In article ,
Tom Veatch wrote:
That marketing approach to power ratings seems to be most often
found in small universal motor applications, but I've also seen
applications using induction motors emblazoned with such things a
"7 HP Developed" and in much smaller lettering "3 HP Running".

Sounds like the same approach used for cheap audio systems,
especially the ones you attach to computers. You know, the ones that
say 200W and are fed from a wall-wart the size of a matchbox.

Sorta, except the audiophools are even more creative. They take the
open circuit voltage times the short circuit current and give it a
technical term lie "music power". If they are really creative
they'll call it "RMS music power" or some other nonsensical term.
It would be like measuring the rotor torque close to stall times the
unloaded RPM.


And they probably "measure" it playing a pure tone at the resonance
frequency of the speaker.

Puckdropper
--
If you're quiet, your teeth never touch your ankles.

To email me directly, send a message to puckdropper (at) fastmail.fm

In article , Puckdropper
puckdropper(at)yahoo(dot)com says...
krw wrote in
t:

In article ,
says...
In article ,
Tom Veatch wrote:
That marketing approach to power ratings seems to be most often
found in small universal motor applications, but I've also seen
applications using induction motors emblazoned with such things a
"7 HP Developed" and in much smaller lettering "3 HP Running".

Sounds like the same approach used for cheap audio systems,
especially the ones you attach to computers. You know, the ones that
say 200W and are fed from a wall-wart the size of a matchbox.

Sorta, except the audiophools are even more creative. They take the
open circuit voltage times the short circuit current and give it a
technical term lie "music power". If they are really creative
they'll call it "RMS music power" or some other nonsensical term.
It would be like measuring the rotor torque close to stall times the
unloaded RPM.


And they probably "measure" it playing a pure tone at the resonance
frequency of the speaker.

Nope. That would give a number that makes at least some sense.

--
Keith