Radar and ultrasonic level instruments

Radar level instruments use electromagnetic signals, while ultrasonic instruments use sound to measure distance to a surface. Their suitability depends on the medium, vessel geometry and conditions along the measurement path.

Typical applications

Storage tanks, process vessels and selected open-channel applications use non-contact level measurement. Guided wave radar is another arrangement where the signal follows a probe.

Types and configuration choices

Compare measuring range, product properties, nozzle geometry, pressure, temperature and output. Foam, vapors, obstructions and surface conditions can influence measurement performance.

Describe the required level result before choosing technology

Identify whether the requirement is continuous level, a point indication, interface information or inventory-related data. Define the result the receiving system needs and the role it plays in the approved installation. Different measurement arrangements address different conditions and outputs. Ask for a technical assessment against the documented duty, rather than treating radar, ultrasonic or guided-wave descriptions as interchangeable product labels for every vessel.

Keep measurement and protective functions explicit. If a separate alarm or protective duty is required, its design and approval basis should be stated in the enquiry. An instrument suitable for routine level information is not automatically accepted for every protective function. The proposal should identify the evidence and responsibilities for the actual requirement without assuming that an advertised feature completes the design of the surrounding system.

Provide a vessel sketch that supports the assessment

Show the measurement location, internals, inlets and other features relevant to the proposed arrangement. Record any chamber or probe interfaces and identify unconfirmed dimensions. Ask which survey or further information is needed before a final configuration is proposed. A useful vessel sketch supports an assessment of the actual installation, while a tank-volume figure or a single exterior photograph can leave essential interfaces undefined.

For a replacement, identify changes in the stored product, nozzle arrangement or operating conditions since the existing instrument was selected. A former configuration may have been assessed for a different duty. Ask the technical response to distinguish retained assumptions from those requiring a new review. The final offer should make limitations visible, especially if part of the required measurement range or process conditions remains unverified.

Agree configuration and commissioning boundaries

Specify the delivered output, reference and configuration information required for the equipment tag. Ask whether site assessment, setup, integration and commissioning are included or provided separately. Request the agreed acceptance records for the actual assignment. The handover should identify outstanding checks and limitations, so a delivered instrument is not treated as a fully accepted level measurement merely because it powers up or communicates with the receiving system.

Tank dimensions and measuring range

Provide a drawing showing vessel dimensions, measurement reference, nozzle position and relevant internal features. State the required measuring range and the level information the receiving system needs. Tank height and usable instrument range are different descriptions, so identify the actual limits and any areas requiring separate review. Ask the technical response to state the installation assumptions used in its assessment. A nominal range alone does not establish that the proposed instrument can measure the required surfaces through the actual vessel arrangement.

Product properties

Describe the material being measured and the process conditions that affect its surface and measurement path. Identify liquids, solids or any required interface between materials, with available property data and known variation. Include foam, vapour, buildup or other conditions documented for the vessel where relevant. Ask the response to explain suitability for the actual duty rather than selecting a technology solely by its name. A capability advertised for one application should not be assumed to apply to every product or installation.

Process pressure and temperature

State the vessel's documented pressure and temperature conditions, including the operating cases relevant to the instrument. Identify external ambient conditions separately from exposure at the process connection. Ask for the applicable limits of the complete offered arrangement, including its process interface and enclosure. A measuring principle's broad application range does not define the limits of every product configuration. Keep assumptions and exceptions visible so the responsible reviewer can evaluate the instrument against the specified location and service.

Nozzle and output requirements

Describe the nozzle dimensions, connection and position, together with any chamber or probe arrangement included in the design. Identify the required output, power supply and receiving-system interface. State whether the enquiry includes mounting accessories, configuration or commissioning services. Ask the offer to identify the exact assembly and the installation information needed for review. A compatible signal output cannot resolve an unsuitable mechanical interface, and a matching flange does not establish that the complete measurement requirement is covered.

How related requirements differ

Pressure gauges and transmitters: Pressure gauges provide local indication, while pressure transmitters convert a pressure measurement into a signal for monitoring or control. Gauge, absolute and differential pressure describe different measurement references that must be matched to the application. Range, overload capability, connection, wetted materials and output distinguish common configurations. Diaphragm seals or other process interfaces may be needed for particular fluids.

Temperature sensors and thermowells: Temperature sensors measure process temperature using elements such as resistance temperature detectors or thermocouples. A thermowell is a protective process connection surrounding a compatible sensor; its material and geometry are part of the mechanical design. Sensor type, insertion length, connection and signal interface must match the installation. Thermowell material, dimensions and the process conditions require separate mechanical review.

Flow meters: Flow meters measure the movement of liquid or gas through a defined path. Different measuring principles respond to volume, mass or related physical properties, so the required measurement basis matters as much as line size. Fluid composition, conductivity where relevant, flow range, available straight runs and required uncertainty influence selection. Specify the output and any calibration or approval requirements.

Compare the complete supply scope

For radar and ultrasonic level instruments, compare the complete assembly and documented scope of supply. An offer for a component may exclude the drive, controls, fittings, accessories or inspection services needed for the installation. List exclusions and proposed alternatives so each quotation can be assessed against the same requirement. Manufacturing origin, delivery location and the supplier's business address are separate facts. If a particular origin is required, request confirmation for the actual offered item and the supporting documentation specified by your project.

Questions before requesting a quotation

What information should be available first? Start with the intended application and the current technical specification for radar and ultrasonic level instruments. In this category, the initial review includes tank dimensions and measuring range, product properties, process pressure and temperature, nozzle and output requirements. Attach the relevant drawings or scope documents and identify any information still awaiting confirmation. This makes it possible to distinguish a preliminary enquiry from a fully defined purchasing or service requirement.

Can an alternative be accepted on size or price alone? A proposed alternative needs review against the required function, materials, interfaces and documented performance. Similar dimensions or a familiar brand name do not establish compatibility. State which requirements are mandatory and where an equivalent may be considered. Availability, lead time and supporting documents are confirmed for the actual offer rather than assumed from this catalogue.