Instrumentation by magnitude

Presión

Presión absoluta, relativa y diferencial para monitoreo de procesos, control de HVAC y verificación de equipos.

Atmospheric pressure is one of the fundamental variables of meteorological and aeronautical observation: pressure reduced to sea level (QNH) and pressure at airfield elevation (QFE) calibrate the altimeters that every flight's safety depends on. In the laboratory, barometric pressure acts as a correction quantity in laser interferometry, gas analysis and calibration standards.

In the process industries, differential pressure is as critical as absolute pressure: the pressure cascades between cleanrooms and adjacent areas are what keep contamination out, and their continuous monitoring is a direct requirement of GMP and ISO 14644 classification.

Use cases

Typical application areas

Professional meteorology and observation networks
Aviation — QNH/QFE pressure and altimeter calibration
Calibration laboratories and transfer standards
Cleanrooms and classified areas — differential pressure cascades
Laser interferometry and lithography systems
Engine test benches and exhaust gas analysis
Data buoys and remote environmental stations
Data loggers and battery-powered systems

Technology

What makes Vaisala's BAROCAP® sensor unique

Schematic cross-section of Vaisala's BAROCAP® sensor: silicon membrane and electrodes over a vacuum gap

BAROCAP® is a micromechanical absolute pressure sensor made of single-crystal silicon. A silicon membrane deforms as pressure changes, altering the height of an internal vacuum gap; the opposite sides of the gap act as electrodes, and the resulting change in capacitance is converted into the pressure reading. Combining single-crystal silicon with capacitive detection yields low hysteresis, excellent repeatability and outstanding long-term stability. First introduced in 1985, the sensor carries genuine space heritage: it has flown on several Mars exploration missions — including NASA's Curiosity rover — and on the Cassini-Huygens mission to Saturn and Titan.