A pressure unit equal to 100 pascals or 0.75 Torr; standard atmosphere is 1013 mbar. European pump and gauge makers, and most labs outside the US, quote ultimate pressures, gauge readings and leak rates in mbar, so leak rates come out in mbar·L/s. It is numerically identical to the hectopascal used in weather reports.
Spec says base below 5E-6 mbar and this controller's set to torr, so convert before you sign it off.
Torr and mbar differ by only a third, so a reading in the wrong unit still looks plausible; check the controller's unit setting before you log a number.
Also heard as
- mbar
- hPa
Related terms
Torr
Pressure unit equal to 1/760 of a standard atmosphere, about 1.333 mbar, and the default in US labs and fabs.
Pascal
The SI unit of pressure, one newton per square metre, used in standards and on calibration certificates.
Micron
Shop name for a millitorr, one thousandth of a Torr, used in US furnace shops, labs and refrigeration work.
Leak rate
Quantity of gas entering a vacuum system through a leak per unit time, usually in mbar·L/s.