Absolute and Gauge Pressure

Absolute and Gauge Pressure

Absolute and gauge pressure measurement covers continuous pressure sensing referenced either to a perfect vacuum (absolute) or to ambient atmosphere (gauge). This category includes pressure transducers and pressure switches that monitor liquids and gases to deliver a real‑time process variable or a discrete alarm/interlock. The reference choice determines how readings shift with barometric pressure and whether vacuum conditions can be represented directly.

Transmitters typically use piezoresistive or ceramic sensing cells coupled to a process membrane and standardized connections. Endress+Hauser’s portfolio spans field instruments and sensor/transmitter assemblies, with interfaces including 0/4–20 mA, HART, PROFIBUS PA, FOUNDATION Fieldbus H1, IO‑Link, and PROFINET over Ethernet‑APL; Bluetooth® Low Energy and an integrated Ethernet web server are available for local access and commissioning.

Benefits center on measurement stability, repeatability, and consistent device diagnostics across an installed base. High accuracy and wide measuring ranges support tight control, while rugged wetted materials and diaphragm seal options extend applicability to aggressive media and elevated temperatures. Where supported, integrated verification/health concepts enable confidence checks without interrupting the process, reducing manual proof testing effort.

Application engineering focuses on matching sensor technology and mechanical design to the service. Absolute devices fit vacuum and low‑pressure gas duties; gauge devices suit most liquid and gas networks; sealed gauge is selected when exposure to atmosphere is undesirable. Flush diaphragms and remote seals mitigate plugging, crystallization, polymerizing fluids, and hygienic requirements, while interface selection aligns with control system and asset management standards.

Typical deployments include reactor and separator pressure control, compressor and air header monitoring, pump suction/discharge supervision, steam and utility distribution, and vessel vapor space pressure for blanketing. Pressure switches provide permissives and high/low trips, while transmitters feed PID loops, condition monitoring, and performance KPIs - supporting equipment protection and consistent product quality.

Miller Mechanical Specialties, an exclusive authorized representative of sales and service for Endress+Hauser.