A certain retail store (Sears) at one time, not too long
advertised a table saw with a 1.5 horsepower electric motor as being
able to proivde "3.0 horsepower maximum developed". Do you know how
they arrive at this without running the risk of a lawsuit for false
advertising? I contacted Sears directly but only got a "run around."
Well, first of all, Sears isn't worried about a suit for false
advertising. Were you to buy a saw and assert that it did not
function as advertised, they could simply replace it or refund your
money and be rid of you. If you sued them, you'd have to prove you
suffered serious financial damage as a result of Sears' grossly
negligent action. *Grossly*, I said: an advertiser is allowed a
certain amount of ``puffing'' in vending his wares. ``Caveat emptor''
is an ancient free-market tradition. Also, if you failed to prevail
in such a suit, you could be ordered to pay Sears' legal expenses,
which would dwarf the cost of all the hardware you will ever buy.
The attorney general in your state might sue Sears, on behalf of
all consumers, if your state law is unusually strict about advertising
contents (which is rare, because of 1st Amendment complications, and
because Sears pays far more taxes and donates far more money to
legislators' re-election campaigns than any number of disgrunted
consumers). That is, if he has attention and attorneys to spare from
pursuing murderers, car thieves, corrupt state employees, credit-card
I don't think Sears is worried.
That being said, here are two ways I can imagine peak power might
differ from average power: (1) the motor could produce 3.0 HP at full
on, but be unable to sustain full on indefinitely without damaging
itself. (2) the motor could produce 3.0 HP under certain unusual or
intermittent conditions of load, electrical power, and so forth, while
producing 1.5 HP under more typical conditions. One would guess the
1.5 HP figure comes from some standard measurement, regulated by some
independent body (UL comes to mind) or the gummint.
I don't know for sure for it could be as simple as the motor can run at
power for short amounts of time, but is unable to get rid of the excess
heat if it
runs that way for too long. So while it is starting up, or for brief
times, it can
be depended on to put out this power, but if you do it for long, it will
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Update: June 2012