Level Sensors

Choosing Level Sensors components

Level sensor technology selection is the first decision and depends on the media, the vessel, and the accuracy requirement. There is no universal level technology — radar excels in steam and dust where ultrasonic struggles, capacitive handles foaming and viscous liquids where ultrasonic and radar may not, and float switches remain simple and reliable where electronic complexity is unwelcome.

Specs to confirm before ordering:

Function: continuous level transmitter (analog or digital), point-level switch (alarm at fixed point), or multi-point controller (high/low/empty)
Technology: ultrasonic (non-contact, sensitive to foam and condensation), 80 GHz radar (non-contact, dust/steam tolerant), capacitive (contact or non-contact, conductive or non-conductive media), vibrating fork (point switch, density-tolerant), conductivity (multi-electrode, conductive liquids only), guided-wave radar (rope or rod in the liquid, foam-tolerant)
Measurement range and accuracy
Process connection: threaded NPT/G, flanged, sanitary tri-clamp
Wetted parts: 316SS, Hastelloy, PTFE, PVDF, depending on media
Process temperature and pressure
Output: 4–20 mA analog, switch contact, IO-Link, HART, Profibus PA, Foundation Fieldbus
Hazardous-area certification if needed (ATEX, IECEx, Class I Div 1/2)
Cable or remote-mount electronics for high-temperature applications

Common gotchas: ultrasonic level transmitters fail on foam — the foam absorbs the acoustic pulse and the sensor reads either empty or wildly fluctuating. Radar sensors require a target large enough to fill the beam at the level; small vessels need careful beam-angle and antenna selection. Capacitive sensors need calibration on the installed media — moving a calibrated sensor to a different liquid usually requires recalibration. Conductivity level controllers work only on conductive liquids; pure water (low TDS) gives unreliable readings.

Typical applications: tank level on water and wastewater treatment, chemical mixing and dosing tanks, bulk-solid level in silos (radar or capacitive), pump dry-run protection (point switch), high-level alarm to prevent overfill, and submersible hydrostatic for well-water level. On legacy installations, in-kind replacement preserves the process connection, mounting depth, and controller scaling.

For obsolete level sensors, send the OEM part number for a sourcing quote.

Do you stock obsolete level sensors?

Yes. Discontinued VEGAPULS first generations, retired Magnetrol Pulsar, end-of-life Endress+Hauser FMR240, and earlier Sick UM30 are sourced through our supplier network.

Radar vs. ultrasonic — which should I pick for tank level?

Radar for steam, dust, vapor, condensation, and foaming environments. Ultrasonic for clean clear-liquid tanks without foam. Radar costs more but handles more environments reliably.

Will the sensor work on foamy liquids?

Guided-wave radar (rope or rod in the liquid) penetrates foam. Free-space radar penetrates most foam types. Ultrasonic fails on foam. Capacitive depends on the foam's dielectric properties.

Do I need a Class I Div 1 hazardous-area version?

Required if the level sensor will be in a Class I Div 1 area (flammable atmosphere always present during normal operation). Div 2 is for occasional presence. Match the original certification — substituting a non-rated sensor in a classified area is a code violation.

Can the sensor be cleaned with caustic or solvent?

Wetted parts compatibility is on the OEM datasheet. PTFE wetted parts handle most caustics and many solvents. Stainless variants handle most non-chloride media. Verify before installation.

What is the warranty?

12-month functional warranty. Wear or chemical attack from incompatible media is not covered.

Baumer FFAK 16NTD1001/L Level Sensor

Baumer FFAK 16PTD1001/L Level Sensor

Baumer FFAK 17NTD1001/L Level Sensor

Baumer FFAK 17NTD1002/L Level Sensor

Baumer FFAK 17PTD1001/L Level Sensor

Baumer FFAK 17PTD1002/L Level Sensor

Baumer FFAM 16PTD1002/L Level Sensor

Baumer FFAM 17PTD1002/L Level Sensor

Baumer FFDK 16P50Y0 Level Sensor

Baumer FODK 23P90Y0/0500 Level Sensor

Baumer LBFS-A1111.0 Level Switch

Baumer UNDK 09G8914 Ultrasonic Level Sensor

Baumer UNDK 09G8914/D1 Ultrasonic Level Sensor

Baumer UNDK 09G8914/IO Ultrasonic Level Sensor

Baumer UNDK 09G8914/KS35A Ultrasonic Level Sensor

Baumer UNDK 09G8914/KS35A/IO Ultrasonic Level Sensor

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