Dear Martin,
As you know the single unit in the International System of Units (SI)
is the joule and this has been the case since the British Association
for the Advancement of Science proposed this unit for energy in 1889.
When I researched the article, 'A word about global warming' (http://
www.metricationmatters.com/docs/AWordAboutGlobalWarming.pdf ), I
collected 93 different words (with 8 556 conversion factors) that are
routinely used to confuse people about energy use in many different
human activities. And this may not be a complete list.
For obfuscation in describing power all you have to do is add (say)
'per second', 'per minute', or 'per hour' after any of these 93
energy measures to make as many of your own power units as you need
to confuse your particular client audience. Calories per minute,
barrels of oil equivalent per second, or British thermal units per
hour are examples. This gives you a choice of 279 measuring word
combinations for power (with 77 562 conversion factors).
Of course if you choose to use the International System of Units (SI)
then your only choice is the watt that is the renamed joule per
second, and there are no conversion factors at all.
Cheers,
Pat Naughtin
PO Box 305 Belmont 3216,
Geelong, Australia
Phone: 61 3 5241 2008
Metric system consultant, writer, and speaker, Pat Naughtin, has
helped thousands of people and hundreds of companies upgrade to the
modern metric system smoothly, quickly, and so economically that they
now save thousands each year when buying, processing, or selling for
their businesses. Pat provides services and resources for many
different trades, crafts, and professions for commercial, industrial
and government metrication leaders in Asia, Europe, and in the USA.
Pat's clients include the Australian Government, Google, NASA, NIST,
and the metric associations of Canada, the UK, and the USA. See
http://www.metricationmatters.com/ for more metrication information,
contact Pat at [EMAIL PROTECTED] or subscribe to
the free 'Metrication matters' newsletter at http://
www.metricationmatters.com/newsletter/
On 2008/02/04, at 2:57 AM, Martin Vlietstra wrote:
In the UK we have a "Very British Mess" when it comes to lawnmower
power
ratings. If you buy a petrol powered machine, the rating will be
in HP, but
if you buy an electric powered machine, the rating will be in kW.
There is
a very good reason not to use HP on electrical machines - the
manufacturer
needs to quote the current drawn by the mower and also many
extension leads
have warnings to the effect that he cable should be unwound if it is
carrying more than 5 amps (US readers - please note that our
electrical
plugs are 230 V, not 115 V.)
I believe that more electrical lawn mowers are sold in the UK than
petrol
lawn mowers. There are a number of reasons:
1) High taxes on petrol
2) Small gardens
3) Petrol engines are not suitable for small lawn mowers.
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf
Of Michael G. Koerner
Sent: 02 February 2008 00:34
To: U.S. Metric Association
Subject: [USMA:40346] No more 'horsepower' on small engines in USA
From the 2008-02-01 Milwaukee, WI Journal-Sentinal (ran on the
front page
below the fold):
http://www.jsonline.com/story/index.aspx?id=713480
"Seems the term, 'horsepower' is going the way of the buggy
By RICK BARRETT
[EMAIL PROTECTED]
Posted: Jan. 31, 2008
When you buy lawn and garden equipment this spring, a familiar old
term -
horsepower - will be missing from many engines.
Blame it on lawyers, or engine makers who might have fudged the
numbers, but
horsepower is no longer the gold standard for small gasoline engines.
Sears, for example, now advertises some lawn mowers rated by
horsepower,
others by torque, and still others by cubic centimeters. And some
mowers
have
no such designation at all.
"Unfortunately, we are not giving consumers the answers they want,"
said
Bill
Rotter, an owner of National Ace Hardware stores in the Milwaukee
area.
There's no longer a horsepower rating for many Briggs & Stratton
engines.
Last
year, Briggs chose torque as its rating system for push mowers, snow
throwers,
pressure washers and generators."
(See link for rest of article)
No mention of watts, but it appears to be a start.
--
___________________________________________ ____
_______________
Regards, | |\ ____
| | | | |\
Michael G. Koerner May they | | | | | |
rise again!
Appleton, Wisconsin USA | | | | | |
___________________________________________ | | | | | |
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