Differential Pressure Measurement in Industry Which device fits which application?

ISO 14644 and GMP Annex 1 (2022) require continuous monitoring of the pressure cascade — typically 10–15 Pa between cleanroom classes. Diaphragm sensors drift over months; the pressure-measuring part of the ring balance contains no diaphragm, no spring, and no components that age — it is physically drift-free.

In ventilation systems, differential pressure across filters indicates contamination level. The ring balance measuring principle does not drift — no readjustment, no zero-point creep. A unique selling point for systems expected to run 20 years without major overhaul.

Industrial furnaces operate with radiant heat and combustion gases. Electronic sensors fail at housing temperatures above 60–80 °C. Ring balances separate the measuring element from the hot process via extended impulse lines — the transmitter can then be installed in a moderate environment (operating temperature up to 50 °C).

In zones with explosive atmospheres, the device must satisfy ignition protection concept Ex ia (Category 1). The RW65_EX_II is the only Rixen product approved for direct installation in Zone 0 and Zone 20. A Zener barrier on the safe side is always required.

Aseptic production areas (EU GMP Annex 1, 2022) require complete pressure documentation. Every re-calibration generates validation effort and OOS risk. Ring balances eliminate re-calibration structurally.

Biogas plants work with moist, H₂S-laden gas — aggressive toward standard materials. Digesters, gas pipelines, and storage are typically classified as Ex Zone 1/2. With the ring balance, the measurement medium does not contact the measuring mechanism, as pressure pulses are routed via separate pipework.