The VEGA VEGAFLEX 81 is a TDR-based guided wave radar sensor for continuous liquid-level and interface measurement. Microwave pulses travel along a probe and are reflected by the product surface or the interface between two liquids. The sensor is suitable for a broad range of liquids and can deliver stable readings in applications where vapor, foam, or condensation may affect other measurement methods. <Cite refs={["turn715418search0","turn715418search2"]} />
Key Features
- Level and interface measurement for a wide variety of liquids
- Cable, rod, and coaxial probe options for different tank geometries and process conditions
- Reliable readings in applications involving vapor, foam, condensation, or buildup
- Suitable for installation in tanks, standpipes, and bypass pipes
- Guided setup and diagnostic functions support commissioning and plant availability
- Measuring range up to 75 m, depending on probe configuration
Applications
- Liquid-level measurement in storage and process tanks
- Interface measurement between two liquids
- Ammonia storage tanks and liquefied gas applications
- Level monitoring in standpipes and bypass chambers
- Chemical, oil and gas, and general process industries
Technical Highlights and Selection Considerations
The VEGAFLEX 81 offers a measuring range of up to 75 m with a cable probe and up to 6 m with rod or coaxial probes. Depending on the selected configuration, the published process temperature range is approximately −40 to +200 °C, and process pressure can range from −1 to +40 bar. The stated measuring accuracy is ±2 mm. Available output options and approvals depend on the selected version. <Cite refs={["turn715418search2","turn715418search20"]} />
When selecting a model, consider the liquid properties, tank height, process temperature and pressure, probe type, installation space, and whether level or interface measurement is required. Confirm the exact operating limits and compatibility against the datasheet for the intended configuration.
Frequently Asked Questions
1. What does the VEGA VEGAFLEX 81 measure?
It measures the continuous level of liquids and can also measure the interface between two liquids.
2. What measurement principle does it use?
It uses time-domain reflectometry (TDR), guiding microwave pulses along a probe and evaluating the reflected signals.
3. What is the maximum measuring range?
The maximum range is up to 75 m with a cable probe. Rod and coaxial versions typically support ranges up to 6 m.
4. Can it operate when vapor or foam is present?
Yes. It is designed to provide reliable measurements in many applications involving vapor, foam, condensation, or product buildup. Actual performance depends on process conditions and installation.
5. Can the VEGAFLEX 81 measure liquid interfaces?
Yes. It can measure the separation interface between two liquids when their dielectric properties and the application conditions are suitable.
6. What probe types are available?
Probe options include cable, rod, and coaxial designs. The appropriate version depends on the measuring range, liquid, and installation conditions.
7. Which output signals are available?
Options include 4–20 mA/HART and selected digital communication protocols, depending on the configuration. Check the relevant datasheet before ordering.
