What is an Absolute vacuum gauge?
An absolute pressure gauge is one that will measure your vacuum system without regard to and independent of local barometric pressure. Many dial (Bourdon) gauges and electronic Transducers reference local barometric pressure as their base measurement. However, since these devices are calibrated at SEA LEVEL conditions, operation of these devices above sea level will cause an erroneous reading. Either the gauge/transducer must be recalibrated for the higher elevation use or an absolute pressure gauge would need to be used.
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