TYCK · APPLICATION CONDITION GUIDE

Tank Level Measurement Application Guide

Tank level measurement determines liquid height, interface or inventory in atmospheric or pressurised vessels. The correct method depends on measurement purpose, vessel dimensions, roof and internals, nozzle geometry, medium density and dielectric behaviour, vapour, foam, agitation, coating, pressure and temperature. Overfill protection and fiscal inventory require separate project and evidence review.

Reviewed

ENGINEERING DECISIONS

Engineering logic for this condition

Define what the level result is used for. Continuous control, local indication, inventory estimation, pump protection and independent high-level protection have different independence, response and evidence requirements. Record minimum and maximum level, interface needs, fill and empty rates, alarm setpoints and failure action. If volume or mass is reported, provide the strapping table, geometry, density basis and calculation ownership rather than equating distance directly with inventory.

Map the vessel and medium. Provide a dimensioned drawing with roof shape, bottom, nozzles, ladders, coils, agitators, stilling wells, inlet streams and nearby obstructions. Describe density and its variation, dielectric behaviour, conductivity, viscosity, foam, vapour, turbulence, coating, condensation, solids and interface layers. Radar, guided wave, hydrostatic, differential-pressure, capacitance and float methods respond differently to those conditions and to installation geometry.

Verify mechanical and process limits for the chosen configuration. Check connection, antenna or probe, measuring span, blocking distances, pressure boundary, temperature, wetted materials and access. Commissioning should record installed geometry, reference point, empty and full limits, false-echo or density settings where relevant, and alarm tests. Suitability and any approval must be supported for the exact sensor, option and protective function.

Selection inputs and technical route

Measurement duty
Control, indication, inventory, interface, pump protection or independent alarm and its required failure action.
Vessel geometry
Height, diameter, roof, bottom, nozzle, stilling well, internals, agitator, coils and filling path.
Medium behaviour
Density, dielectric value, conductivity, viscosity, foam, vapour, coating, solids and interface stability.
Operating envelope
Level range, pressure, vacuum, temperature, fill rate, agitation, condensation and environmental exposure.
Evidence and commissioning
Configuration limits, drawings, calculation ownership, reference points, settings and functional test records.

Applications for engineering review

  • Atmospheric storage where vessel geometry, vapour, foam, filling stream and required inventory conversion are defined.
  • Pressurised process vessels where pressure-temperature limits, internals, agitation and interface behaviour are documented.
  • Pump-control or high-level duties where setpoints, failure state, independence and proof-test responsibilities are specified.

Limitations and confirmation points

  • One level technology does not cover every combination of foam, vapour, density change, coating, internals and interface.
  • A continuous level indication is not automatically an independent overfill-protection system or fiscal inventory measurement.

APPLICATION RFQ

Information to send for configuration review

  1. Continuous, interface, alarm or inventory purpose
  2. Minimum and maximum level and setpoints
  3. Dimensioned tank and nozzle drawing
  4. Internals, agitator, coils and filling stream
  5. Medium, density and dielectric behaviour
  6. Foam, vapour, condensation, coating and solids
  7. Pressure, vacuum and temperature envelope
  8. Connection, materials, output and failure state
  9. Volume or mass calculation and commissioning needs
  10. Quantity and required approval or drawing records

Request a configuration-specific review

APPLICATION FAQ

Frequently asked questions

Which tank drawing details are needed before selecting a level instrument?

Show vessel height and diameter, roof and bottom shape, nozzle size and length, mounting position, ladders, coils, agitators, stilling wells, inlet streams and the minimum and maximum levels. Mark the reference point and any inaccessible zones. Add pressure, temperature and connection ratings. These details expose possible echo obstructions, probe contact, dead zones, elevation effects and service-access limits before a product family is shortlisted.

How do foam and vapour affect tank level technology?

Their effects depend on the sensing principle, foam thickness and conductivity, vapour composition, pressure, condensation, dielectric contrast and signal path. Some foam attenuates a free-space radar echo, while hydrostatic methods instead depend on density and pressure reference. Provide actual observations across operating states. The selected antenna, probe, frequency, mounting and settings should be reviewed and commissioned against the real vessel rather than a generic foam label.

Can a tank level transmitter provide inventory in mass or volume?

It can supply a level input, but volume needs a validated vessel geometry or strapping table, and mass also needs a representative density. Temperature or composition may change that density. Define where the conversion occurs, which data source is authoritative, the units and required uncertainty. Calibration and reference-point errors also carry into the inventory result. Preserve the calculation method and revision with the instrument and tank records.