Size of Heat Pump in Tons

tom baker

First Chief Moderator
Staff member
I have a Payne Heat pump and would like to know how many "tons" capacity it is. its a
Product PH12NA036000ABAA
Model PH12NA036-B

About ten years old and I have the manual but not sure what to look for
 

winnie

Senior Member
Look for the cooling capacity in BTU per hour. 12000 BTU per hour is 1 ton of cooling.

At a guess I'd say the unit is 36000 BTU per hour and thus 3 tons of cooling, just from the model number, not from any real knowledge.
 

electricman2

Senior Member
Look for the cooling capacity in BTU per hour. 12000 BTU per hour is 1 ton of cooling.

At a guess I'd say the unit is 36000 BTU per hour and thus 3 tons of cooling, just from the model number, not from any real knowledge.
My thoughts too. The 036 in the Model No. is a clue
 

topgone

Senior Member
I have a Payne Heat pump and would like to know how many "tons" capacity it is. its a
Product PH12NA036000ABAA
Model PH12NA036-B

About ten years old and I have the manual but not sure what to look for
Please search the web using the model #. My search yielded 34,400 BTUh rating (036-B) or a TC of 2.87 tons. Here.
 
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MAC702

Senior Member
Whether the actual is 34,400 BTU or 36000 BTU, it's all still considered a 3-ton system, and the model number will almost always have a "036" in it somewhere.

Below 2-tons, you'll usually just see the BTUs listed, and these would typically be window or mini-split systems. After those, the residential world is divided into tonnage as 2, 2.5, 3, 3.5, 4, and 5. Multiply by 12 and that's the number you'll usually find in the model number.
 

junkhound

Senior Member
Just noticed than no one yet explained the obvious to OP (if not already known by him), that the 12,000 BTU/hr is the heat that needs to be removed from water to make a ton of ICE.
 

drcampbell

Senior Member
Last week wired up an 18,000 BTU mini-split and it only weighed about 300 pounds :p:p
Short pounds or long pounds?

... 12,000 BTU/hr is the heat that needs to be removed from water to make a ton of ICE.
Um, no. "12,000 BTU/hour" isn't even a measure of heat; it's a measure of power. The amount of heat that needs to be removed from a ton of water to turn it into ice is closer to 300 kBTU than twelve. And it's BTU, not BTU per hour.

About a century and a half ago, in the early days of mechanical refrigeration, icehouse operators asked refrigeration salesmen, "What'll this do for me?" Their response: "This machine will provide the same cooling effect as consuming a ton of ice every day." And the refrigeration ton was born.

But we no longer use icehouses. It would be a good thing if we also quit using refrigeration tons.
(HVACR engineers are among the slowest to adopt new ideas ... if something introduced in 1799 can still be considered "new". Many of them still use Roman Numeral prefixes.)

<rant>
One more example of a good reason to ditch the British system of weights & measures and use metric.

In the metric system, there are only seven base units to learn and just ONE unit of refrigeration capacity, the Watt, (or kilowatt, megawatt, et at.) No confusion and no need for unit conversion.
(there's also ONE unit of efficiency, the dimensionless ε -- no need to fart around with EER, SEER, COP or kW/ton)

https://en.wikipedia.org/wiki/Intern...ystem_of_Units
</rant>
 
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drcampbell

Senior Member
I don't understand how an engine is rated in Kw.
Multiply torque (in kiloNewton-meters) by speed. (in radians per second) The result is the engine's power output in kilowatts.

The Watt is a measure of power. All flavors of power, not merely electric power.
 
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junkhound

Senior Member
Short pounds or long pounds?


Um, no. "12,000 BTU/hour" isn't even a measure of heat; it's a measure of power. The amount of heat that needs to be removed from a ton of water to turn it into ice is closer to 300 kBTU than twelve. And it's BTU, not BTU per hour.

[/url]
</rant>
Yes, thanks for the good clarification - I should have been more specific - e.g makes 1 ton of ice per day. 144 BTU/pound *2000 = 288,000 BTU. Divide by 24 = 12,000 BTU/hr.
 

Besoeker3

Senior Member
<rant>
One more example of a good reason to ditch the British system of weights & measures and use metric.

In the metric system, there are only seven base units to learn and just ONE unit of refrigeration capacity, the Watt, (or kilowatt, megawatt, et at.) No confusion and no need for unit conversion.
(there's also ONE unit of efficiency, the dimensionless ε -- no need to fart around with EER, SEER, COP or kW/ton)
Yes, it has it's merits and I've been advocating that on here for years!
Just one small correction. Although commonly, and incorrectly, called metric, it is SI. (Système Internationale d'Unités,)
You can't measure Joules by the metre.
 

MAC702

Senior Member
Nothing wrong with "metric system." Metrics are measurements of things, not necessarily lengths. You can use a formal foreign name if you wish, but it's not incorrect to use a name that more people actually understand.

Just one small correction: "its" has no apostrophe when used as a possessive pronoun.

Besoeker3 said:
Yes, it has it's merits and I've been advocating that on here for years!
Just one small correction. Although commonly, and incorrectly, called metric, it is SI. (Système Internationale d'Unités,)
You can't measure Joules by the metre.
 

Besoeker3

Senior Member
Nothing wrong with "metric system." Metrics are measurements of things, not necessarily lengths. You can use a formal foreign name if you wish, but it's not incorrect to use a name that more people actually understand.

Just one small correction: "its" has no apostrophe when used as a possessive pronoun.
You are correct. No apostrophe. I don't normally make many grammatical mistakes. Please accept my apology.
But the term "metrics" has a different meaning to "metric system".

Anyway, I'm an old fellow. I grew up with Imperial measures. Yards, feet, inches, chains, furlongs, leagues, bushels, acres, etc. At secondary school (age eleven onward) science was in the CGS system. Centimetre, gram, second. Later, and at university, we had MKS. Then SI. All my engineering calculations used that.

But we Brits still want Imperial units for some things. Ask someone their height and you will most likely get an answer in feet and inches, their weight in stones and pounds.
An interesting anomaly is found at the British pub. If I have a beer, it is sold by the pint. My dear wife has a wine and that's measured in millilitres.
 

drcampbell

Senior Member
... Just one small correction. Although commonly, and incorrectly, called metric, it is SI. (Système Internationale d'Unités,) ...
Right you are. I took a wild guess that this audience -- particularly the Americans here -- would vaguely recognize the "metric" system, but have an eyes-glaze-over moment were I to mention SI.
 

winnie

Senior Member
As I get older I find that I am inherently oppositional. I push people in my lab to use Newton meters for torque and radians per second for speed (it helps when one is writing the experiment control software...) At the same time when I am forced to use _metric_ (not SI units) I get ornery and ask for thinks like dodecimeters of stuff.

When I am told _use metric_ and then have to deal with 'pressure' in kg/cm^2, or speed in km/hr my CDO goes haywire (CDO, its kinda like OCD, but the letters are in proper order....)

And then I remember that while SI is a self consistent system of units, the units themselves are pretty arbitrary and their selection quite political. Think about our unit of length; given what we know now, using the distance light travels in 1/1,000,000,000 second _exactly_ as the unit of length would be much nicer than the distance light travels in 1/299,792,458 second.

Sorry, just rambling :)
 

Besoeker3

Senior Member
When I am told _use metric_ and then have to deal with 'pressure' in kg/cm^2, or speed in km/hr my CDO goes haywire (CDO, its kinda like OCD, but the letters are in proper order....)

And then I remember that while SI is a self consistent system of units, the units themselves are pretty arbitrary and their selection quite political.
Sorry, just rambling :)
Ramble on, sir.
But can you shed a light on why you think the units have a political aspect?
 

winnie

Senior Member
Ramble on, sir.
But can you shed a light on why you think the units have a political aspect?
'The nice thing about standards is that you have so many to choose from.'

One critical aspect of units of measurement is how technically sound they are, how reliably they can be implemented or derived from basic physical quantities, how self consistent the units are, etc. By this metric, SI is hands down better than imperial units.

But a separate critical aspect is how well you can convince people to _use_ the same system of units. And convincing people to _use_ units is at its core a political act.

Is there any _technical_ benefit to making 0 longitude Greenwich rather than Paris? That selection was politics.

Is there any _technical_ benefit to the particular unit of length used in SI?

Sometimes the politics is in a very small group of people, eg. the recent vote to redefine the kilogram in terms of Plank's constant rather than something else.

IMHO technical standards are by their nature political things, and this is true for standards for units of measure.

-Jon
 

GeorgeB

ElectroHydraulics engineer (retired)
I push people in my lab to use Newton meters for torque and radians per second for speed. At the same time when I am forced to use _metric_ (not SI units) I get ornery and ask for thinks like dodecimeters of stuff.

When I am told _use metric_ and then have to deal with 'pressure' in kg/cm^2, or speed in km/hr my CDO goes haywire (CDO, its kinda like OCD, but the letters are in proper order....)
what's a dodecimeter? Google didn't help me.<grin mode on>

radians per second is ROTARY speed, not linear; I don't understand your opposition to km/hr unless you just want to use primary units like meters/second ... or cm/sec? I see it now, speed limit something m/sec.

On pressure, would kgf satisfy your opposition, or do you want to get to Newtons/cm^2 ... a derived unit, don't we need Newtons/m^2? Or does cgs sufficiently allow cm^2?

I'm in the control of industrial fluid power world ... we think of bar as the "metric" pressure unit ... ??? and volume is in liters, not m^3 <grin mode off>
 

junkhound

Senior Member
what's a dodecimeter? probably a type, should have been duodecimeter? Then same divisor as feet to inches, etc? Babylonian base 12 system.

As far as pressure, SI is Pa, Pascals (SP?) just to obfuscate the discussion.
 

Besoeker3

Senior Member
But a separate critical aspect is how well you can convince people to _use_ the same system of units. And convincing people to _use_ units is at its core a political act.

-Jon
I disagree. The whole world apart from USA and Myanmar use SI. It makes it easier for international trade to have a common system.
 

drcampbell

Senior Member
... As far as pressure, SI is Pa, Pascals (SP?) just to obfuscate the discussion.
I'm not sure what's obfuscatory about that. Pressure is force per unit area. In SI, that's Newtons/meter², and it was given a unique name because pressure is so frequently measured.
 

StarCat

Senior Member
'The nice thing about standards is that you have so many to choose from.'

One critical aspect of units of measurement is how technically sound they are, how reliably they can be implemented or derived from basic physical quantities, how self consistent the units are, etc. By this metric, SI is hands down better than imperial units.

But a separate critical aspect is how well you can convince people to _use_ the same system of units. And convincing people to _use_ units is at its core a political act.

Is there any _technical_ benefit to making 0 longitude Greenwich rather than Paris? That selection was politics.

Is there any _technical_ benefit to the particular unit of length used in SI?

Sometimes the politics is in a very small group of people, eg. the recent vote to redefine the kilogram in terms of Plank's constant rather than something else.

IMHO technical standards are by their nature political things, and this is true for standards for units of measure.

-Jon
This is well stated and I will add a few things.....
The Metric System is based on " false " abstractions which make it an inherently " inharmonic system."
Napolean saw it and knew the trouble had started even while in exile. Its was started by policitican and for reasons of monetary control.
I remember the utility of it in the Chem lab. if you go digging on the subject you may be shocked to find out that it is in fact not so good at a great many thiings.
Bar is " Bar none " the stupidest unit of measure I have ever encountered, and useless for HVACR applications, yet there are confused people writing Mollier diagrams with it.
What this is doing is creating division and things that cannot be read by people who are well versed in Imperial units.
The metric system needs to be moved out of the USA, lock stock and barrel, and otherwise Violently Resisted.
I do not want it and there are others, though small in number who are in accord. It has created nothing but time wasting problems in my life and I have little to no use for it.
People at large need to get that some few are tired of having this thing forced on them.
 

gadfly56

Senior Member
what's a dodecimeter? probably a type, should have been duodecimeter? Then same divisor as feet to inches, etc? Babylonian base 12 system.

As far as pressure, SI is Pa, Pascals (SP?) just to obfuscate the discussion.
An extinct unit of measure, flightless, and previously distinguished by its apparent stupidity.
 

winnie

Senior Member
This is well stated and I will add a few things.....
The Metric System is based on " false " abstractions which make it an inherently " inharmonic system."
Napolean saw it and knew the trouble had started even while in exile. Its was started by policitican and for reasons of monetary control.
I remember the utility of it in the Chem lab. if you go digging on the subject you may be shocked to find out that it is in fact not so good at a great many thiings.
Bar is " Bar none " the stupidest unit of measure I have ever encountered, and useless for HVACR applications, yet there are confused people writing Mollier diagrams with it.
What this is doing is creating division and things that cannot be read by people who are well versed in Imperial units.
The metric system needs to be moved out of the USA, lock stock and barrel, and otherwise Violently Resisted.
I do not want it and there are others, though small in number who are in accord. It has created nothing but time wasting problems in my life and I have little to no use for it.
People at large need to get that some few are tired of having this thing forced on them.
I know that you are partially agreeing with me, but I believe that you take it a step too far.

SI is a perfectly valid self consistent system of units. Lots of effort has gone in to tying things together so that we don't have the problem of Watts and horsepower and tons and btu/hr etc. all being different units for the same measurement.

It is beautiful that you can multiply force times speed and get power with a conversion factor of 1.

I simply believe that a system of units is arbitrary and to some extent the selection of the _particular_ units is political, in the specific sense that not only do you need to pick a set of units, but for utility you need to convince others to use the same units. Agreeing with other people to use specific units, legislating the use of specific units, standards organizations defining units, etc. is a political process.

-Jon
 

junkhound

Senior Member
Did not meter of today start with French revolution?

Have also seen theories that prehistoric henge builders used the meter, determined by using strings, sticks, an artificial horizon, the movement of stars, and using a meter long pendulum to determine star transit times to tie it all together.
 

drcampbell

Senior Member
... The Metric System ... has created nothing but time wasting-problems ...
People at large need to get that some few are tired of having this thing forced on them. ...
OK, Gramps.

What's your suggestion? Quit doing business with everybody in the world except Myanmar and Liberia?

In case you're not payin' attention, nobody's "forcing" anything on you. You don't want to use it, don't use it. But that also means not using imported machinery, vehicles or parts. And not doing business with people or corporations that do. That's a pretty big sacrifice for the privilege of clinging to the past, but you're free to do so.

The problem isn't the metric (Système Internationale d’Unités) system; it's trying to use two systems simultaneously. Or more than two, if you count all the variations in the British system. (short tons, long tons, refrigeration tons, BTU/hour, registry tons (100 feet[SUP]3[/SUP]), tons of energy (tons of TNT equivalent), ... ) And the solution isn't eliminating SI; it's finally eliminating the archaic & provincial British system.
 

gadfly56

Senior Member
Did not meter of today start with French revolution?

Have also seen theories that prehistoric henge builders used the meter, determined by using strings, sticks, an artificial horizon, the movement of stars, and using a meter long pendulum to determine star transit times to tie it all together.
Yes, we can blame the French for this one. ;) It was originally supposed to be one ten millionth the distance from the equator to the North Pole along a Great Circle through Paris.
 

kwired

Electron manager
Yes, we can blame the French for this one. ;) It was originally supposed to be one ten millionth the distance from the equator to the North Pole along a Great Circle through Paris.
I believe all SI units are based on Earth constants in one way or another. Many reference a property of water I believe. A kilogram of water is 1 cubic decimeter of water I believe (at a certain temp).

I also seem to recall a gram of water has a volume of one milliliter which is also one cubic centimeter.

Units of force and mass are pretty much same numbers in Earth's gravity, and terminology is wrongly used at times, but we get away with it because they are usually the same numerical values on Earth
 

Besoeker3

Senior Member
The problem isn't the metric (Système Internationale d’Unités) system; it's trying to use two systems simultaneously. Or more than two, if you count all the variations in the British system. (short tons, long tons, refrigeration tons, BTU/hour, registry tons (100 feet[SUP]3[/SUP]), tons of energy (tons of TNT equivalent), ... ) And the solution isn't eliminating SI; it's finally eliminating the archaic & provincial British system.
It pretty much is in Britain. But we still stick with pints and miles per hour.
 

kwired

Electron manager
It pretty much is in Britain. But we still stick with pints and miles per hour.
But most your shorter linear measurements are commonly in meters, centimeters or millimeters, right? Or is yards,feet and inches still pretty common?
 

Besoeker3

Senior Member
But most your shorter linear measurements are commonly in meters, centimeters or millimeters, right? Or is yards,feet and inches still pretty common?
I think most people know what they are but if you buy, say a piece of furniture dimensions are in centimetres. Meds are in mg. Bottled water in in litres or ml. Carrots are in kg.
 

kwired

Electron manager
I think most people know what they are but if you buy, say a piece of furniture dimensions are in centimetres. Meds are in mg. Bottled water in in litres or ml. Carrots are in kg.
So "everyday" linear measurements for most people are done in SI units. Meaning a common tape measure is marked in SI units, here it is kind of rare to find a tape measure that is marked in SI units only. Not that you can't buy one, just not many have one and those that do have one probably don't use it very often.
 

Besoeker3

Senior Member
So "everyday" linear measurements for most people are done in SI units. Meaning a common tape measure is marked in SI units, here it is kind of rare to find a tape measure that is marked in SI units only. Not that you can't buy one, just not many have one and those that do have one probably don't use it very often.
I can't speak for most people. Might be an age/generation thing.
The steel tapes I have are dual marked.

 
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Frank DuVal

Senior Member
One more example of a good reason to ditch the British system of weights & measures and use metric.

In the metric system, there are only seven base units to learn and just ONE unit of refrigeration capacity, the Watt, (or kilowatt, megawatt, et at.) No confusion and no need for unit conversion.
No confusion??????????????:?

You must be young!:p

SO, I get a cooling system rated in killowatts. How does that help me wire it? DIvide KW by system voltage to get amps? I thought so, it is still read the nameplate! Now I have a product with TWO killowatt ratings. That is not confusing?:?

Much clearer with Killowatts being the amount of electricity consumed and the cooling ability in BTU or tons.

Same with motors/engines rated in horsepower. I know what a 300 HP engine does in a car. I have to convert to use KW of engine.

Cubic inch to liters is not too hard, a factor of 60.8. After 35 years most have learned what size engines are in liters.

Maybe in another 35 years when we are gone young guys will speak of KW in cars, but not yet here!:thumbsup:

By then cars will be electric and KW will seem so more applicable anyway.

In the mean time, I need some device boxes to fit those 50.8 x 101.6 studs. Easier, right!:lol:
 

Frank DuVal

Senior Member
If you stuck with SI there would be no conversion required.....
Stuck with? We did stick with HP. :happyyes: Youse guys changed! All the old British iron is rated in horsepower. Even taxed on Tax Horsepower back then.;) Hence way the long stroke small diameter cylinders were all the rage back then, as Tax Horsepower was derived from a math formula instead of actual performance data....
 

Besoeker3

Senior Member
Stuck with? We did stick with HP. :happyyes: Youse guys changed! All the old British iron is rated in horsepower. Even taxed on Tax Horsepower back then.;) Hence way the long stroke small diameter cylinders were all the rage back then, as Tax Horsepower was derived from a math formula instead of actual performance data....
Engine power here is still quoted in horsepower. I don't know why.
 

PaulMmn

Senior Member
The 'problem' with the metric system is that so many teachers are very concerned about converting from one system to the other. Yuck!

Don't convert! Remember that one Mars probe that crash landed because some units were metric and some English? https://www.latimes.com/archives/la-xpm-1999-oct-01-mn-17288-story.html

Some things are easy to 'convert' when needed: A meter is a yard, more or less. For any approximations, 100 meters is a football field long. A foot is 30 cm (300 mm)(0.3 meter).

Most automobile components are metric; although some are still English. We buy bottles of soft drinks in 1 or 2 liter bottles. Milk still comes in quarts, half- and full-gallons. Cans of beverages are still 12 fluid ounces. My model train track comes in metric sizes, but the packaging has English conversion units on it. Double-yuck!

And those 50.8 x 101.6 studs-- that's a 'rounding error.' Let the lumber yards loose, and they'll be 50 x 100 studs. The rest will be lost because they were''planed after drying.' Space those studs 400 cm apart (that's a hair less than 16") or 600 cm (~24").

Pick one standard and stick with it for the duration of the project!
 

MAC702

Senior Member
...here it is kind of rare to find a tape measure that is marked in SI units only. ....
A client loaned me his tape measure yesterday. It was marked solely in inches on the tape. I was doing an inside measurement, and went to verify the added length of the body of the tape measure itself. It said "+ 76mm"
 

Carultch

Senior Member
About a century and a half ago, in the early days of mechanical refrigeration, icehouse operators asked refrigeration salesmen, "What'll this do for me?" Their response: "This machine will provide the same cooling effect as consuming a ton of ice every day." And the refrigeration ton was born.

But we no longer use icehouses. It would be a good thing if we also quit using refrigeration tons.
(HVACR engineers are among the slowest to adopt new ideas ... if something introduced in 1799 can still be considered "new". Many of them still use Roman Numeral prefixes.)
It only accounts for the cooling effect as 1 ton of 0C ice turns into 0C water, i.e. the latent heat of fusion. That happens to be where (within the heat energy diagram) that most of the energy absorption occurs in the H2O. It doesn't account ice that starts below 0C having to absorb energy to get to 0C in the first place, and it doesn't account for any temperature gain the water has after it melts.
 

Carultch

Senior Member
SO, I get a cooling system rated in killowatts. How does that help me wire it? DIvide KW by system voltage to get amps? I thought so, it is still read the nameplate! Now I have a product with TWO killowatt ratings. That is not confusing?:?

Much clearer with Killowatts being the amount of electricity consumed and the cooling ability in BTU or tons.

Same with motors/engines rated in horsepower. I know what a 300 HP engine does in a car. I have to convert to use KW of engine.
When both input and output ratings are in kilowatts, and specified so you can see which is which, it TELLS YOU SOMETHING about what is happening within the machine. It shows you the inputs and outputs, so you can compare both power ratings on the same scale of numbers. Having separate units for electric power, mechanical power, thermal power, etc, obscures this information. Physical reality is that no machine is 100% efficient at turning the energy we put in the machine into energy we want out of it.

We expect a motor to have some power lost to heat, and we expect an engine of the same capacity to have a lot more power lost to heat and exhaust. Refrigeration systems are a different stroy, because they extract power from either the cooling space, or surrounding cold environment in the case of heat pumps, and generally can "pump" more thermal power from cold space to hot space, than the electric power needed to supply them.
 

Carultch

Senior Member
And those 50.8 x 101.6 studs-- that's a 'rounding error.' Let the lumber yards loose, and they'll be 50 x 100 studs. The rest will be lost because they were''planed after drying.' Space those studs 400 cm apart (that's a hair less than 16") or 600 cm (~24").
The metric-using countries, identify dimensional lumber by actual size, rather than nominal. What a concept!

The closest equivalent of 2x4, is 35x90, and their lumber is close in actual size to inch-nominal standard lumber sizes, rounded to multiples of either 5 or 10 mm. Plywood and drywall come in 1200 mm x 2400 mm, which is what a 4'x8' sheet would be, when rounded to the nearest 100 mm. Multiples of 100 mm, such as 400 mm and 600 mm, are common for standard spacing of studs, joists and rafters.
 

drcampbell

Senior Member
No confusion??????????????:?
You must be young!:p

SO, I get a cooling system rated in killowatts. How does that help me wire it? DIvide KW by system voltage to get amps? I thought so, it is still read the nameplate! Now I have a product with TWO killowatt ratings. That is not confusing?:?

Much clearer with Killowatts being the amount of electricity consumed and the cooling ability in BTU or tons. ...

In the mean time, I need some device boxes to fit those 50.8 x 101.6 studs. Easier, right!:lol:
If using multiple different units to measure the same thing wasn't confusing, this thread wouldn't exist.

Born 1959.
You'll wire it the same way you do now: by the CURRENT consumption on the nameplate. Minimum circuit capacity, maximum fuse size. Not by the power it delivers and not by the power it consumes.

My forecast: By the time we finally drop the British system of weights and measures, we will also be in the habit of displaying the ACTUAL dimensions of things. One (?) of the big box stores is already doing this as a result of a lawsuit claiming it was false advertising to call a wall stud a "2x4" when in reality, it's actually 28% less than that. But I ain't holding my breath; it takes 50-100 years for the building industry to adopt a "new" idea. (for example: the far-superior Torx hexalobular screwhead (ISO 10664) was developed in 1967)

Stuck with? We did stick with HP. Youse guys changed! All the old British iron is rated in horsepower. Even taxed on Tax Horsepower back then. Hence way the long stroke small diameter cylinders were all the rage back then, as Tax Horsepower was derived from a math formula instead of actual performance data....
Ah, yes ... yet another example of a cockamamie indirect measurement. Not only is it peculiar and not terribly reality-based, (British tax horsepower is a measure of the total area of the piston tops) but it's also defined differently in different jurisdictions.

This particular example has nothing to do with which unit system was selected; it's an example of a rule imposed by people who just didn't have a clue about the art & science of measurement itself. It would have been equally stupid -- and had the same unintended consequences -- had it been defined in SI.
https://en.wikipedia.org/wiki/Tax_horsepower

Of course, lots of dimensions are still nominal rather than actual. ...
That should be one of the FIRST things corrected. It's SO much fun to try to explain to newbies that you can't fit a "3-inch" pipe in a "4-inch" stud space.

[The refrigeration ton] only accounts for the cooling effect as 1 ton of 0°C ice turns into 0°C water, i.e. the latent heat of fusion. ... It doesn't account ice that starts below 0°C having to absorb energy to get to 0°C in the first place, and it doesn't account for any temperature gain the water has after it melts.
Right you are. But I doubt anybody was being that precise in the 1800s, when the refrigeration ton was defined.
I also doubt it caused much of an error in practice. Natural ice -- harvested from ponds & rivers and capped with an insulating layer of snow -- was probably never much below 0°C, and since it's cold in an icehouse, the meltwater was probably never much above 0°C when it was discarded.
 
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Besoeker3

Senior Member
If using multiple different units to measure the same thing wasn't confusing, this thread wouldn't exist.

Born 1959.
You'll wire it the same way you do now: by the CURRENT consumption on the nameplate. Minimum circuit capacity, maximum fuse size. Not by the power it delivers and not by the power it consumes.



Right you are. But I doubt anybody was being that precise in the 1800s, when the refrigeration ton was defined.
I also doubt it caused much of an error in practice. Natural ice -- harvested from ponds & rivers and capped with an insulating layer of snow -- was probably never much below 0°C, and since it's cold in an icehouse, the meltwater was probably never much above 0°C when it was discarded.
Interesting that you are using centigrade.......but your weather is given in Fahrenheit..........
 

drcampbell

Senior Member
I'm almost completely bilingual.
I also live just 16 km north of the Canadian border, and often travel there and/or tune into Canadian broadcasting.
 

Besoeker3

Senior Member
I'm almost completely bilingual.
I also live just 16 km north of the Canadian border, and often travel there and/or tune into Canadian broadcasting.
Most unit conversions I can do mentally. Maybe that makes me bilingual too?
I've been to Canada numerous times. From St Johns Island off the east coast to Vancouver Island off the west coast. In fact, it took longer to fly from London to Ottawa than it took to fly across Canada.

Mostly variable speed drives on cranes on icebreakers. Getting back to units, they were rated at 275kW

I digress.
 

drcampbell

Senior Member
... it took longer to fly from London to Ottawa than it took to fly across Canada. ...
Typo? I would think it would take less time to cross the Atlantic than to cross Canada. (I presume you're not referring to London, Ontario or London, Ohio) There are many, many jokes about the vastness (and flatness) of the Canadian prairies and many, many awe-struck reports about the vastness (and grandeur) of the Canadian Rockies.

The Winnipeg comedy festival is one of the best on Earth. Likely because Manitoba winters give you lots of time to huddle indoors and polish your material.
 

kwired

Electron manager
No confusion??????????????:?

You must be young!:p

SO, I get a cooling system rated in killowatts. How does that help me wire it? DIvide KW by system voltage to get amps? I thought so, it is still read the nameplate! Now I have a product with TWO killowatt ratings. That is not confusing?:?

Much clearer with Killowatts being the amount of electricity consumed and the cooling ability in BTU or tons.

Same with motors/engines rated in horsepower. I know what a 300 HP engine does in a car. I have to convert to use KW of engine.

Cubic inch to liters is not too hard, a factor of 60.8. After 35 years most have learned what size engines are in liters.

Maybe in another 35 years when we are gone young guys will speak of KW in cars, but not yet here!:thumbsup:

By then cars will be electric and KW will seem so more applicable anyway.

In the mean time, I need some device boxes to fit those 50.8 x 101.6 studs. Easier, right!:lol:
IEC electric motors are rated in kW - it is the output rating though.

Knowing displacement of an ICE doesn't tell you the output rating, though if you know much about them it likely gives you a ballpark estimate of it's rating.
 

Besoeker3

Senior Member
Typo? I would think it would take less time to cross the Atlantic than to cross Canada. (I presume you're not referring to London, Ontario or London, Ohio) There are many, many jokes about the vastness (and flatness) of the Canadian prairies and many, many awe-struck reports about the vastness (and grandeur) of the Canadian Rockies.

The Winnipeg comedy festival is one of the best on Earth. Likely because Manitoba winters give you lots of time to huddle indoors and polish your material.
You are right again.

This might give you, and others, an idea of what I did............I've removed company names so maybe the mods will permit it.

 
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