Hydrostatic Level

Hydrostatic Level

Hydrostatic level measurement provides continuous level indication in liquid applications by using pressure sensors to infer head height. The sensor measures the hydrostatic pressure at a defined point and converts it to level once liquid density and reference conditions are applied. Endress+Hauser’s Deltapilot and Waterpilot pressure transmitters address these duties in tanks and wells, with configurations that can be submerged or mounted externally on a vessel.

The technology is built around measuring cells designed for wet, demanding environments. The Contite sensor is described as especially developed for hydrostatic level measurement, with the measuring element hermetically sealed between the process membrane and measuring membrane to protect the sensor and electronics during severe moisture and condensate formation. Ceramic, oil-free capacitive cells are also offered; in a “dry” ceramic cell the process pressure acts directly on a robust ceramic diaphragm and the resulting capacitance change is measured.

These constructions translate into practical benefits. A condensate-proof Contite measuring cell is positioned for maximum plant safety, with very good reproducibility and long-term stability even after temperature shocks. Ceramic cells add extremely good chemical compatibility and high mechanical stability through ultra-pure 99.9% ceramic, and robust ceramic membranes can include integrated breakage detection and suitability for vacuum services.

Hydrostatic methods are straightforward to engineer, but accuracy depends on getting the reference right. Open tanks require a stable atmospheric reference (often via vented cabling in submersible probes), while closed vessels require compensation for vapor-space pressure. Density variation from temperature or concentration changes can be handled by applying compensation, selecting an appropriate measurement range, or choosing a cell technology that tolerates process transients without drift.

Typical applications include level in process and storage tanks, sumps, and pits; well and reservoir monitoring; and water/wastewater lift stations where submersible installation is preferred. Hydrostatic sensors are often selected when vapor, foam, or surface turbulence complicates non-contact methods, and when a rugged pressure-based measurement is desired across food, environmental, and general process services.

George E. Booth Co., an exclusive authorized representative of sales and service for Endress+Hauser.