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PS rating
3

PS rating

PS rating

(OP)
Can anyone tell me what PS means when refered to in car engine power??

I understand it to be pferdestarke or something similar...but what does this word mean and what units is it??

Friar Tuck of Sherwood

RE: PS rating

I can see the P, as it is the first letter in the word Power, but I recall that Horse starts with an H.

Thus we used to use HP for Horse Power.

What is the S for?

RE: PS rating

PS is the german abbreviation of horse power, namely "Pferde-Stärken" (pferde = horses, stärke = power).

hth,
chris

RE: PS rating

I have a 1959 "National Tank" book of conversion factors.  Pferde Starke x 1.0 = Cheval Vapeur, or Metric Horsepower, and Horsepower Metric x 0.9863 = Horsepower US.

Larry

RE: PS rating

(OP)
I wonder what a metric horse looks like?

Friar Tuck of Sherwood

RE: PS rating

And what exactly is a metric horse?

RE: PS rating

That's easy, it's got ten legs.

RE: PS rating

friartuck
Maybe it's output is meter'd.

pennpoint

RE: PS rating

(OP)
groan

Friar Tuck of Sherwood

RE: PS rating

2
James Watts horsepower camee from the work a horse could do. He figured a typical horse could lift a 180 pound weight on a rope walking in a 24 foot diameter circle 144 times per hour.
Calculating this you get about 32572.03 pounds feet per minute. Its a nasty figure coming from pi being involved in the circumference of the circle, so he was generous to the horse when defining the power of his steam engines, and he rounded it up to 33000 pounds (force) feet per minute.
That is one horsepower.

The german equivalent is 75 kilograms force metre per second.

1 g acceleration is defined 9.80665 m/s².
So it comes out to 75*9.80665 = 735.49875 Watts.

Since an inch is defined as 2.54 centimeters and 12 inches make a foot, and a pound is defined as 1/2.205 kg and there are 60 seconds in a minute, and not bothering with the definition of gravity, we get

2.54*0.01*12*(1/2.205)*33000*(1/60)g is a horsepower
ie 76.027210884 g Watts. (g=9.80665)

And the Germans say a horsepower (Pferdstärke) is 75g Watts, abbreviated PS.

Its probably easier to work in metric units, but if the Americans like their Gallon to be 3 inches by 7 inches by 11 inches, 231 cubic inches, that's fine by me.

RE: PS rating

So then the Germans don't actually have a horse?

RE: PS rating

The metric horse with 10 legs is still only a concept. No one has ever been able to catch one.

HAZOP at www.curryhydrocarbons.ca

RE: PS rating

I sell them. Contact me. But please be careful. This is not an authority approved sale.

Btw: metric horses have only nine legs, the tenth has a different function ;)

RE: PS rating

owg, must be kind of like a unicorn, or maybe an unobserved marsupial.

Larry

RE: PS rating

(OP)
Crylstalclear

Thanks for the definition. I assume the Germans simply took the nearest rounded up equivalent to the 736W HP to make life easy??

To complicate matters, Is the HP the same as BHP (My friend tells me that there is a difference between Horse power and brake horse power)

Friar Tuck of Sherwood

RE: PS rating

For geologists a "horse" is a large rock caught along a fault. When it falls, it exerts horse power.

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