From Windhues-at-unidui.uni-duisburg.de Thu Jul 15 13:15:14 1999 From: Thorsten Windhues Well..... definitions first.... 1 Pa (Pascal) = 1 N/m2 (Newton/square meter) 1 at (technical atmosphere) = 1 kp/cm2 with 1 kp = "weight force" of a one kg mass at sea level 1 atm (physical atmosphere) = atmospheric pressure at sea level 1 torr = pressure of 1 mm mercury Now.... conversions..... 1 bar = 100000 Pa (Pascal) = 1.0197 at (technical atmosphere) = 0.98692 atm (physical athmosphere) = 0.75006E03 torr 1 Pa = 10E-05 bar = 1.0197E-05 at = 0.9869E-05 atm = 0.75006E-02 torr 1 at = 0.980665E05 Pa = 0.980665 bar = 0.96784 atm = 0.73556E03 torr 1 atm = 1.01325E05 Pa = 1.01325 bar = 1.03323 at = 760 torr 1 torr = 1.3332E02 Pa = 1.3332E-03 bar = 1.3595E-03 at = 1.3158E-03 atm Finally... for the Americans... 1 PSI (pound per square inch) = 1/14.70 atm OK, here comes my comment on the gauge readings in the MB's: The gauge show what we Germans call "bar Ueberdruck". This means that the gauge reading shows the pressure above atmoshperic pressure. 0 means the oil pressure is identical to the current air pressure. If the gauge shows 2 bar, the absolute oil pressure would be 2 bar + the current outside pressure. Assuming the pressure pump developes a constant absolute pressure means that we have different gauge reading in dependance of the height. A car driven at sea level would show a lower pressure value than the same car in the Himalaya because the air pressure at sea level is higher than in the mountains. Bye, Thorsten Windhues (at about 200 m above sea level) At 12:29 15.07.99 -0700, you wrote: >ok, help me out here... > >what exactly is a "bar"... no bad jokes please... > >Is it "one atmospheric pressure"? If so, is it compensated for altitude >and barometric pressure? What is one altitude anyways, 14.8 something or 15 psi??? > >thanx, >john From Farnes_Quinn-at-Allergan.com Thu Jul 15 13:21:22 1999 From: Farnes_Quinn Well, if you pass one up on your way home, your wife will consider you virtuous, and if you happen to ground your aircraft carrier on one, it will cost you your command. But for the purposes of this list, one Bar is one atmosphere measured at sea level. It is the height of a column of mercury in an old-fashioned mercury barometer (hence the name) of something like 29.98 inches, which in metric units is 760 millimeters (mm), also called 760 milliTorr. In British units, it's 14.7 psi. q. > -----Original Message----- > From: john [SMTP:john-at-cafe.johnmeister.com/jeep/sj] > Sent: Thursday, July 15, 1999 12:30 PM > To: Thorsten Windhues > Cc: diesel-benz-at-digest.net > Subject: a bar =? > > ok, help me out here... > > what exactly is a "bar"... no bad jokes please... > > Is it "one atmospheric pressure"? If so, is it compensated for altitude > and barometric pressure? What is one altitude anyways, 14.8 something or > 15 psi??? > > thanx, > john > ---- > > ------------------------------------------------------------------------- > john-at-johnmeister.com/jeep/sj **** Snohomish, Washington USA > don't leave life without jesus, please... > http://johnmeister.com/jeep/sj/john > http://johnmeister.com/jeep/sj > ------------------------------------------------------------------------- > > >