Radar level transmitters measure the level of liquids and bulk solids without touching the medium, which makes them a first choice for continuous measurement in storage tanks, process vessels and silos. This guide explains how radar level measurement works, what to check when selecting a model, and how the Endress+Hauser Micropilot range maps to typical applications.
How Radar Level Measurement Works
A FMCW radar transmitter emits a continuous wave with an upward-sweeping frequency, then measures the frequency difference between transmitted and reflected signals to calculate distance. Because the signal travels at the speed of light and is not affected by pressure, temperature or most vapour layers, radar provides stable measurement across a wide range of process conditions. Modern 80 GHz devices focus the beam more narrowly, which gives better performance in tanks with small nozzles, agitators or internal fittings and allows smaller antennas.
Key Selection Criteria
Before choosing a model, confirm these application points:
- Measuring range and tank height – each antenna style has a defined maximum range; bulk solids need a wider beam or dedicated 80 GHz versions.
- Nozzle diameter and length – 80 GHz radars with small antennas fit narrow nozzles (from DN50) that older 26 GHz devices cannot handle.
- Medium properties – dielectric constant, surface behavior, foam, dust, build-up and strong turbulence.
- Process temperature and pressure – from hygienic CIP/SIP cycles to high-temperature vessels.
- Hygienic requirements – EHEDG / 3-A certified versions with hygienic process connections for food, pharma and biotech.
- Hazardous area approvals and output – 4-20 mA HART, or digital protocols for remote monitoring.
Which Micropilot Model Fits Which Application
| Application | Typical model | Why |
|---|---|---|
| Basic liquids, water and wastewater | Micropilot FMR10B, FMR20B | Compact 26 GHz radar for simple applications and cost-sensitive installations |
| Simple liquid applications | FMR30B / FMR60B | 80 GHz with narrow beam, ideal for most tanks with small nozzles |
| Narrow nozzles and agitators | FMR62B | Smallest 80 GHz antenna, handles installations where space is tight |
| Hygienic processes | FMR63B | Hygienic design with EHEDG and 3-A approvals for food and pharma |
| Bulk solids and silos | FMR67B | 80 GHz radar with specially shaped antennas for dust and long ranges |
| Process industry, wider range | FMR51 | 16 GHz with horn or parabolic antennas for larger tanks |
Replacing an Existing Radar Level Transmitter
The most reliable starting point is the full order code from the nameplate. Compare the process connection, antenna size, supply voltage, output signal and approval before assuming a like-for-like replacement. If you are changing from a 26 GHz to an 80 GHz device, check the nozzle size and measuring range – most upgrades fit existing flanges, but the antenna geometry differs. Send us the nameplate photo if the order code is damaged; our team confirms the order code and any configuration changes needed.
How to Get a Quotation
Share the application data from the checklist above or the order code from your existing device through the Request Quotation page, or send details via Technical Support. We confirm the correct configuration, check availability and return a quotation with delivery time for your destination country.
Related guides: Differential Pressure Transmitter Guide and Hygienic Vibronic Level Switch Guide.