Level Sensors & Level Switches
Continuous and point-level measurement in tanks, silos, sumps and process vessels, including foaming, condensing and aggressive media.
Need a specific variant?
Ranges, threads, connectors and cable lengths can be modified at the factory from 50 pieces.
Request a quote Ask an engineerLead time5-14 days
CalibrationIncluded
Custom buildFrom 50 pcs
Level measurement problems usually trace back to the surface, not the electronics. Foam absorbs ultrasound, condensation blinds optics, and a build-up on a capacitive probe changes the dielectric constant until the reading drifts. Our answer is to match the technology to the surface behaviour rather than to the vessel dimensions alone.
Radar handles most of the difficult cases: 80 GHz units focus a narrow beam that ignores tank walls and internal structures, and they read through foam and vapour that would defeat an ultrasonic sensor. Ultrasonic remains the cost-effective choice for clean water and simple sumps. Capacitive and vibrating fork switches cover point-level duties such as high-high alarms, pump protection and dry-run interlocks.
All continuous models output 4-20 mA with HART or Modbus, and the point-level switches are available with relay, PNP or NAMUR output. Process connections range from G1/2 thread to DN100 flange, with PTFE and PFA coatings for acids and solvents.
Range Overview
Level Sensors variants
Each variant exists because a different application needs it. The distinction is usually mechanical or environmental rather than a better accuracy figure.
Radar Level Transmitters
80 GHz80 GHz non-contact measurement to 30 m with ±3 mm accuracy, unaffected by vapour, dust and most foam.
Ultrasonic Level Sensors
0.3-12 mCost-effective non-contact measurement for water, wastewater and clean liquids from 0.3 to 12 m.
Capacitive Level Sensors
Point + continuousRod and cable probes for liquids and powders, with adjustable sensitivity for build-up compensation.
Vibrating Fork Switches
NAMUR / relayPoint-level detection independent of dielectric constant, used for high and low alarms and dry-run protection.
Float & Magnetic Switches
No powerSimple, power-free switching for sumps, reservoirs and coolant tanks, with reed or mechanical contacts.
Catalogue
Level Sensors in stock and made to order
DM-LF120-CAP
DM-LF120 Capacitive Level Switch for Liquids and Powders
DM-LR60-RD-30M
DM-LR60 80 GHz Radar Level Transmitter, 0-30 m
Technical Range
Typical specifications
Figures below are the range across the family, not a single model. Specify the exact range, accuracy and connection on the quote request and we will confirm which variant meets it.
Request a specification check| Parameter | Typical |
|---|---|
| Measuring range | 0.3 m to 30 m |
| Accuracy | ±3 mm (radar) / ±0.25% FS (ultrasonic) |
| Beam angle | 4° / 8° / 12° |
| Process temperature | -40 to +150 °C |
| Process pressure | -1 to 40 bar |
| Output signal | 4-20 mA, HART, Modbus RTU, relay, PNP |
| Supply voltage | 18-36 VDC |
| Wetted material | 316L, PTFE, PVDF |
| Ingress protection | IP67 / IP68 |
| Certifications | CE, RoHS, ATEX, IECEx |
Applications
Where this family is used
Storage and buffer tanks
Continuous inventory measurement with 4-20 mA to the DCS and a local display for operators.
Wastewater sumps and wet wells
Ultrasonic or radar level with pump alternation logic in the controller, plus a float switch as independent high-level protection.
Silo and hopper inventory
Radar through dust and on angled surfaces, with volume conversion for bulk solids.
Chemical dosing tanks
PTFE-coated capacitive probes and non-contact radar for acids, caustics and solvents.
Selection Guide
How to specify correctly
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1
Look at the surface, not just the tank
Foam, condensation, agitation and build-up determine whether radar, ultrasonic or a contact probe will work. A drawing of the vessel internals saves a site visit.
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2
Check the dielectric constant for contact probes
Capacitive sensors need a minimum dielectric constant. Below it, the probe reads the air above the liquid as product.
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3
Separate protection from control
Use an independent point-level switch for high-high alarm, never the same continuous transmitter that drives the control loop.
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4
Plan the mounting boss
Radar needs a clear, unobstructed path. A standpipe or a nozzle that protrudes into the tank creates a false echo that no configuration can remove.
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5
Confirm hazardous area classification
Ex ia versions are available across the radar and switch ranges, and the barrier requirement differs between Zone 0 and Zone 1.
Used in these industries
All industries →FAQ
Level Sensors questions
Radar or ultrasonic, which is better for a tank with foam?
Radar. Foam absorbs the ultrasonic pulse and can produce a reading that looks stable but is wrong. 80 GHz radar penetrates most foam layers and returns an echo from the liquid surface, which is why we recommend it for fermentation, flotation and chemical reactors.
How close to the tank wall can a radar sensor be mounted?
With an 80 GHz narrow-beam unit, 100 mm from the wall is usually enough on a tank wider than 1 m. The rule is to keep the beam clear of nozzles, ladders and heating coils; the beam angle printed on the datasheet tells you the cone diameter at maximum range.
Can a level sensor measure through a closed metal tank?
No. Radar and ultrasonic both need a non-metallic window or an open nozzle. For sealed metal vessels, use a guided-wave radar probe or a differential pressure method instead.
What output do you recommend for pump control?
A 4-20 mA continuous signal for the control loop plus an independent vibrating fork switch for high-high protection. Relying on a single instrument for both duties is a common cause of overflow incidents.
Do you supply flanges and hygienic connections?
Yes. Standard connections are G1/2, G1 and DN50 flange; tri-clamp and Varivent are available for food and pharmaceutical tanks, with 3-A compliant surface finishes.
Other product families
Tell us the application and we will confirm the right variant.