8H3B

The measuring system operates on the Coriolis principle. The Coriolis force acts on an object moving in a straight line within a rotating system. Fc = 2 · ∆m (ν · ω) Fc = Coriolis force ∆m = mass of the moving object ω = angular velocity ν = radial velocity of the object in the rotating or oscillating system The magnitude of the Coriolis force depends on the mass \(\Delta m\) of the moving object and its radial velocity v, i.e. the mass flow rate. Instead of a rotating system with constant angular velocity \(\omega\), the sensor adopts oscillating measuring tubes.Fluid flows through the sensor. Two parallel measuring tubes inside the sensor oscillate in antiphase, similar to a tuning fork. The Coriolis force generated within the measuring tubes creates a phase shift in tube oscillation: • At zero flow (fluid at rest), the two measuring tubes oscillate in‑phase with no phase difference. • Mass flow accelerates oscillation at the inlet of the measuring tubes and decelerates oscillation at the outlet, producing a phase shift.The higher the mass flow rate, the larger the phase shift. Electromagnetic phase sensors record the oscillation phase at the inlet and outlet of the measuring tubes. Antiphase oscillation of the two measuring tubes ensures system balance. The measuring principle is completely independent of temperature, pressure, viscosity, electrical conductivity and fluid‑specific properties.

Measurement of corrosive fluids

High‑precision Promass H is dedicated to heavy‑duty corrosion‑resistant applications and ensures high safety for measuring chemically corrosive fluids. Featuring a compact transmitter, Promass H 300 delivers a high degree of flexibility in operation and system integration: single‑sided access, remote display and improved connection options. Heartbeat Technology consistently guarantees process safety. • Measuring principle independent of fluid physical properties (e.g. viscosity and density) • High‑accuracy liquid and gas measurement for applications with maximum corrosion‑resistance requirements