http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf a conversion table
for A/c tons is at the end of the article

Excerpt: Ton (Cooling)
A measurement of heat energy commonly used historically to measure heat
loads
in North America. A ton is equal to 12,000 BTUs and is the amount of heat
energy required to melt
2000 pounds (907kg) of ice in one hour. This is an archaic term typically
used to specify heat output when
expressed in Tons/day, where the use of the more modern term Watts is the
simpler and more universal
measure that should be used. Conversions from Tons to Watts are provided at
the end of this paper.

A/c tons represent a truly archaic term. Needless to say, the rest of the
world has been using the much simpler and more elegant metric system for the
last 200 years. Only the following countries do not use the metric system:
United States, Liberia, and Myanmar. Looks like Americans cannot cope with
the simplicity of grams and kilograms. They struggle with fractions of feet,
chains, rod and miles, instead of using simple millimeters, centimeters,
meters and kilometers.

http://en.wikipedia.org/wiki/Metric_system

--
Walter
www.rationality.net
-
"Abe" wrote in message
...
I tried looking it up on the web, but couldn't find anything that
describes exactly what it means.





--
Posted via a free Usenet account from http://www.teranews.com

http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf writes:

A ton is equal to 12,000 BTUs and is the amount of heat
energy required to melt
2000 pounds (907kg) of ice in one hour.

Amazing that APC is publishing such stupidity as this. This would flunk
high school physics. Even a public school.

On Wed, 11 Jul 2007 21:09:00 -0700, Walter R. wrote:

http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf a conversion table
for A/c tons is at the end of the article

A/c tons represent a truly archaic term. Needless to say, the rest of the
world has been using the much simpler and more elegant metric system for the
last 200 years. Only the following countries do not use the metric system:
United States, Liberia, and Myanmar.

Horsepower is just as archaic, is not a part of the metric system, and the
whole world has no problem using it.

In article ,
"Walter R." wrote:

Looks like Americans cannot cope with
the simplicity of grams and kilograms. They struggle with fractions of feet,
chains, rod and miles, instead of using simple millimeters, centimeters,
meters and kilometers.


Yeah, my girlfriend struggles with the chains while I struggle with the
rod. Damn these imperial units.

"Horsepower" is an extremely sloppy technical designator. How many different
versions of horsepower are there, including the original one horse power?
Nobody knows precisely what your refer to, when you are using the term
"horsepower". The sales department and the technical departments have
different ideas as to what constitutes a "horsepower". That's what happens
when we use archaic descriptive terms. We should strive for precision in
language. Why not use the universal and unambiguous Watt?

http://en.wikipedia.org/wiki/Horsepower

--
Walter
www.rationality.net
-
"Karl S" wrote in message
.. .
On Wed, 11 Jul 2007 21:09:00 -0700, Walter R. wrote:

http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf a conversion
table
for A/c tons is at the end of the article

A/c tons represent a truly archaic term. Needless to say, the rest of the
world has been using the much simpler and more elegant metric system for
the
last 200 years. Only the following countries do not use the metric
system:
United States, Liberia, and Myanmar.

Horsepower is just as archaic, is not a part of the metric system, and the
whole world has no problem using it.



--
Posted via a free Usenet account from http://www.teranews.com

Walter R. wrote:
"Horsepower" is an extremely sloppy technical designator.
Why not use the universal and unambiguous Watt?

Watts alone don't tell you how much *useful* work can be accomplished.
For that you also need some sort of efficiency rating.

Chris

Smitty Two wrote:
Looks like Americans cannot cope with
the simplicity of grams and kilograms. They struggle with fractions of feet,
chains, rod and miles, instead of using simple millimeters, centimeters,
meters and kilometers.

Yeah, my girlfriend struggles with the chains while I struggle with the
rod. Damn these imperial units.

he he he

--
Message posted via http://www.homekb.com

On Jul 12, 1:43 am, "Walter R." wrote:
"Horsepower" is an extremely sloppy technical designator. How many different
versions of horsepower are there, including the original one horse power?
Nobody knows precisely what your refer to, when you are using the term
"horsepower". The sales department and the technical departments have
different ideas as to what constitutes a "horsepower". That's what happens
when we use archaic descriptive terms. We should strive for precision in
language. Why not use the universal and unambiguous Watt?

You can put everything in metric and SI units but you get numbers that
you cannot relate to.
Funny that my UK friends are mostly metric but still measure their
body weight in stones
Frank

Personally, I don't struggle with any of those measurements.

Steve Barker







"Walter R." wrote in message
...
A/c tons represent a truly archaic term. Needless to say, the rest of the
world has been using the much simpler and more elegant metric system for
the last 200 years. Only the following countries do not use the metric
system: United States, Liberia, and Myanmar. Looks like Americans cannot
cope with the simplicity of grams and kilograms. They struggle with
fractions of feet, chains, rod and miles, instead of using simple
millimeters, centimeters, meters and kilometers.

According to Chris Friesen :
Walter R. wrote:
"Horsepower" is an extremely sloppy technical designator.
Why not use the universal and unambiguous Watt?

Watts alone don't tell you how much *useful* work can be accomplished.
For that you also need some sort of efficiency rating.

Watts used as motor _output_ ratings. Efficiency is irrelevant
to how much work you can produce. If the motor _produces_ 1Kw,
that's how much work it can do, regardless of the efficiency.

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

According to Richard J Kinch :
http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf writes:

A ton is equal to 12,000 BTUs and is the amount of heat
energy required to melt
2000 pounds (907kg) of ice in one hour.

Amazing that APC is publishing such stupidity as this. This would flunk
high school physics. Even a public school.

Indeed. For those who didn't catch it, a ton of ice takes the
same amount of energy to melt, regardless of how long it takes.

[Especially when you notice the other posting that says "of ice
in 24 hours..."]
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

Chris Lewis wrote:
According to Chris Friesen :
Walter R. wrote:
"Horsepower" is an extremely sloppy technical designator.
Why not use the universal and unambiguous Watt?
Watts alone don't tell you how much *useful* work can be accomplished.
For that you also need some sort of efficiency rating.

Watts used as motor _output_ ratings. Efficiency is irrelevant
to how much work you can produce. If the motor _produces_ 1Kw,
that's how much work it can do, regardless of the efficiency.

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

"Shaft", "Net" or "Belt" HP is output power, too...it doesn't matter
what the units are, it's _where_ it's measured.

--

Chris Lewis wrote:

According to Richard J Kinch :

http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf writes:


A ton is equal to 12,000 BTUs and is the amount of heat
energy required to melt
2000 pounds (907kg) of ice in one hour.

Amazing that APC is publishing such stupidity as this. This would flunk
high school physics. Even a public school.


Indeed. For those who didn't catch it, a ton of ice takes the
same amount of energy to melt, regardless of how long it takes.

[Especially when you notice the other posting that says "of ice
in 24 hours..."]

Careful! You might miss a high school physics question too.
Unfortunately, a Refrigeration ton is is sometime a unit of power,
and sometimes a unit of energy.
As a unit of power, (in the US) it is 12000 BTU per HOUR, which is
also approximately the amount of power required to melt one ton
(2000 pounds) of ice per DAY.
That is also called a "commercial ton of refrigeration".

As a unit of energy ("standard ton of refrigeration"), it is 288,000 BTUs,
which is approximately the energy required to melt 2000 pounds of
ice. (not a rate, so no time units here).

See:


http://en.wikipedia.org/wiki/Ton#Uni...ergy_and_power
http://www.sizes.com/units/ton.htm#ton_of_refrigeration
http://home.att.net/~numericana/answ....htm#othertons

On Jul 12, 11:14 am, (Chris Lewis) wrote:
According to Richard J Kinch :

http://www.apcmedia.com/salestools/T..._EN.pdfwrites:

A ton is equal to 12,000 BTUs and is the amount of heat
energy required to melt
2000 pounds (907kg) of ice in one hour.

Amazing that APC is publishing such stupidity as this. This would flunk
high school physics. Even a public school.

Indeed. For those who didn't catch it, a ton of ice takes the
same amount of energy to melt, regardless of how long it takes.

[Especially when you notice the other posting that says "of ice
in 24 hours..."]
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

Yeah, it's shame that a company document that tauts itself as
"Explanation........for IT Professionals" would contain such sloppy
info

I guess that's one the benefits of wikipedia....peer correction

I was under the impression (or at least this is the way my circle of
engineers referred to a/c capacity)

a "ton of a/c" was derived from that amount of heat required to be
"removed" to generate a ton of ice....(since an a/c is a means to
remove heat)

then (for the sake of "defining" a/c capacity) this quantity was
spread over a 24 hr period to give a heat removal rate in BTU/hr

SO since the heat of fusion for water (from memory is ~144 btu / lbm)
thus a ton of ice (water) needs a total heat removal of 288,000 btu

divided by 24hrs yields 12,000 btu / hr

so a one ton a/c unit has the heat removal capacity of 12,000 btu /
hr


wrt to SI or Imperial units ......some things still haven't made the
jump to SI (even in the metric world)


cheers
Bob

On Thu, 12 Jul 2007 18:11:56 -0000, Chris Lewis wrote:

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

I didn't know that. What are some of the countries where GASOLINE engines
are rated in watts or kilowatts?

Karl S wrote:
On Thu, 12 Jul 2007 18:11:56 -0000, Chris Lewis wrote:

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

I didn't know that. What are some of the countries where GASOLINE engines
are rated in watts or kilowatts?

How about Germany? They also measure DIESEL engines' output in kW.

On Fri, 13 Jul 2007 01:41:02 GMT, Beowulf wrote:

Karl S wrote:
On Thu, 12 Jul 2007 18:11:56 -0000, Chris Lewis wrote:

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

I didn't know that. What are some of the countries where GASOLINE engines
are rated in watts or kilowatts?

How about Germany? They also measure DIESEL engines' output in kW.

In Germany it's Pferdestärke, or PS.

I'm not sure about all diesel engines, that's why I emphasized GASOLINE. I
know that many diesels, especially the gigantic ones they use on ships, in
power plants, etc., were rated in kW. Like the ones from this interesting
German company:
http://www.manbw.com/

According to Karl S :
On Thu, 12 Jul 2007 18:11:56 -0000, Chris Lewis wrote:

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

I didn't know that. What are some of the countries where GASOLINE engines
are rated in watts or kilowatts?

Perhaps I should have said that a bit different - most of the
countries that are officially metric (which is most countries)
will not be using HP for anything, except informally.

Do a google search for "kw engine power", and you'll see countries
all over the world (JP, AU, KR, SE, DE, UA, PL etc) using Kw, often
alone, or sometimes with a horsepower rating in brackets.

Not just diesels. I saw a australian web pages with stihl weedwacker
specs that only quoted kilowatts.

Most people in Canada are familiar with horsepower, not watts of
mechanical energy, but government regulation/documents produced
since metrification I believe are in watts and kw.

The Owner's manual for our car gives both.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.

On Thu, 12 Jul 2007 13:50:38 -0500, dpb wrote:

Chris Lewis wrote:
According to Chris Friesen :
Walter R. wrote:
"Horsepower" is an extremely sloppy technical designator.
Why not use the universal and unambiguous Watt?
Watts alone don't tell you how much *useful* work can be accomplished.
For that you also need some sort of efficiency rating.

Watts used as motor _output_ ratings. Efficiency is irrelevant
to how much work you can produce. If the motor _produces_ 1Kw,
that's how much work it can do, regardless of the efficiency.

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

"Shaft", "Net" or "Belt" HP is output power, too...it doesn't matter
what the units are, it's _where_ it's measured.

My motor has a shaft and a belt. Do I need a net too?

:
: A ton is equal to 12,000 BTUs

CY: Correction. that's 12,000 BTU per hour.

and is the amount of heat
: energy required to melt
: 2000 pounds (907kg) of ice in one hour.

CY: Wrong. Rate of heat required to melt a ton in 24 hours.

:
: Indeed. For those who didn't catch it, a ton of ice takes the
: same amount of energy to melt, regardless of how long it takes.
:
: [Especially when you notice the other posting that says "of ice
: in 24 hours..."]
: --
: Chris Lewis,

CY: However, a ton specifies the rate of 24 hours.

288 000 BTU / 24 Hrs 12000 BTU / Hr
1 Ton of water = 2000 Lbs 144 BTU / Lb
= 288 000 BTU = 3.52 kW = 3520 J / s
= Total BOREDOM = WOT U WONT
TO KNOW FOR ANYWAY WOT R U
A MASOCHIST
"Karl S" wrote in message
.. .
On Thu, 12 Jul 2007 18:11:56 -0000, Chris Lewis wrote:

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

I didn't know that. What are some of the countries where GASOLINE engines
are rated in watts or kilowatts?

It's an American archaic term that the Knights of the Round Table invented.
A ton is 7 KW.

http://www.apcmedia.com/salestools/T...XPED_R1_EN.pdf

--
Walter
www.rationality.net
-
"Telstra" wrote in message
...
288 000 BTU / 24 Hrs 12000 BTU / Hr
1 Ton of water = 2000 Lbs 144 BTU / Lb
= 288 000 BTU = 3.52 kW = 3520 J / s
= Total BOREDOM = WOT U WONT
TO KNOW FOR ANYWAY WOT R U
A MASOCHIST
"Karl S" wrote in message
.. .
On Thu, 12 Jul 2007 18:11:56 -0000, Chris Lewis wrote:

As an example, much of the rest of the world doesn't use "HP" for
gasoline engines - engines are rated in watts or kilowatts. It's
output power.

I didn't know that. What are some of the countries where GASOLINE engines
are rated in watts or kilowatts?





--
Posted via a free Usenet account from http://www.teranews.com