Vacuum gauges are pressure measuring instruments that measures pressure in a vessel operating at sub-atmospheric pressure. Depending on the type of vacuum system and the required operating vacuum level, different vacuum gauges (or combinations) are required, to determine and control the vacuum level of the vacuum chamber at any precise moment in time.
“In terms of engineering and science, it is hard to over-emphasise the importance of measurements. They are the very essence of these two disciplines, which we use to explain the otherwise unexplainable with equations, tables, graphs and figures. In turn, this allows us to compare, contrast, repeat and define the apparent chaos which defines our world.”
Source: Vacuum Science World