Radar (FMCW) level transmitter for agitated and corrosive liquids

  • Continuous, non-contact level measurement in harsh environments
  • 24 GHz radar, Horn or Drop antennas
  • Measuring range: 0…100 m / 328 ft
  • -50…+200°C / -58…+392°F, up to +700°C / +1292°F in non-ex applications; -1…100 barg / -14.5…1450 psig (higher on request)
  • Icon/Logo Security Integrity Level 2/3 (SIL 2/3)

OPTIWAVE 7400 with DN80 / 3" PEEK Drop antenna

OPTIWAVE 7400 C –  24 GHz radar (FMCW) level transmitter for agitated and corrosive liquids

The OPTIWAVE 7400 is a 2-wire 24 GHz radar (FMCW) level transmitter for liquids in harsh environments like tanks with agitators containing corrosive media. It is particularly designed for continuous, non-contact level measurement under extreme conditions prevalent in the chemical, petrochemical, power, metal or oil and gas industry. The device features Metallic Horn antennas as well as PTFE and PEEK Drop antennas for measuring distances up to 100 m / 328 ft. The Drop antennas are perfectly suited for aggressive liquids in tanks. In applications with toxic and dangerous products, this radar device can be equipped with a METAGLAS® second sealing barrier.

The OPTIWAVE 7400 provides accurate readings even in processes with fast changing levels. It has approvals for hazardous areas and can be used in process conditions of up to +200°C / +392°F and 100 barg / 1450 psig. There is also a dedicated version available for non-ex applications with molten salt or other high temperature liquids up to +700°C / +1292°F. The radar level transmitter comes with a quick coupling system, allowing the converter to be removed under process conditions and upgrade obsolete radars in high-end applications, e.g. to obtain extended device features. The OPTIWAVE 7400 features extensive device diagnostics (acc. to NE 107) as well as HART®7 communication.

Product highlights

  • 2-wire, loop-powered, with HART®7
  • Distance piece for non-ex applications with molten salt or other high temperature liquids of up to +700°C / +1292°F
  • PTFE or PEEK Drop antennas:
    • Insensitive to condensation
    • Small beam angle (4° with DN150 / 6″ PTFE antenna)
    • Ellipsoidal shape and smooth surface to minimise scaling
    • PTFE flange plate protection for corrosive media
    • New DN100 / 4" Drop antenna for distances up to 80 m / 262.5 ft
  • 316L Metallic Horn antennas with optional purging system
  • Heating / cooling systems to prevent crystallisation or build-up in Metallic Horn antennas
  • ±2 mm / ±0.08″ accuracy
  • METAGLAS® second sealing barrier for toxic and dangerous liquids
  • Antenna extensions to suit any nozzle length
  • Empty tank spectrum function eliminates false reflections caused by tank internals
  • Large choice of flange and thread connections
  • Quick Coupling system permits removal of the converter under process conditions and 360° rotation for easy reading of display
  • Converter compatible with all OPTIWAVE 7300 C flange connections
  • Large, backlit LCD screen with 4-button keypad for operation with bar magnet; no need to open the housing cover
  • PACTware™, HART® DD and DTM provided free of charge with full functionality
  • Extensive device diagnostics acc. to NAMUR NE 107
  • SIL 2/3 certified for safety-related applications
  • 3-year warranty

Typical applications


  • Level measurement in/on process tanks, reactors (max. 100 m / 328 ft) and open air applications (floating roofs etc.)
  • Agitated liquids in tanks
  • Processes with fast changing levels (≤60 m/min / 196.85 ft/min)
  • High accuracy applications
  • Non-Ex applications up to +700°C / +1292°F (e.g. molten salt in solar plants)

Chemical industry

  • Alcohols, e.g. methanol, ethanol
  • Solvents, acids, bases
  • Additives
  • Butadiene
  • Ethylene, propylene
  • Molten sulphur

Petrochemical industry, oil and gas industry

  • Liquefied gases
  • Hydrocarbons and fuels
  • Benzene
  • Hydraulic oils
  • Condensates

Power industry

  • Molten salt at Concentrated Solar Power plants (CSP)

Iron, steel and metal industry

  • Molten steel batching

Product variants

BM 26A 5000 OW 7400

OPTIWAVE 7400 with BM26A-5000

Radar (FMCW) level transmitter with bypass chamber

  • All-in-one solution with FMCW radar and bypass chamber
  • Large choice of bypass chamber materials e.g. 316L, 304L, alloy C276, alloy 625
  • Level measurement up to 5.5 m / 18 ft (other dimensions on request)
  • Ideal for difficult process conditions, e.g. turbulence, foam

Accessories for this product


Handheld for in-depth verification, device commissioning and monitoring

  • On-site performance check and verification (level 0,1,2) without process interruption
  • Convenient commissioning of field devices, e.g. zero calibration
  • Detailed reports for proof test documentation of safety loops acc. to IEC 61508/61511, and for quality management systems (ISO 9001)

View product details
Wall-mounted bracket

Wall-mounted bracket

Antenna aiming kit for OPTIWAVE level transmitters

  • L-shaped bracket to attach radar level transmitters firmly to a wall
  • Only suitable for radars with G1 or G1½ process connection
  • Material: Stainless steel (1.4404 / 316L)
  • Bracket length: 250mm / 9.84”

Hanging bracket

Hanging bracket

Antenna aiming kit for OPTIWAVE level transmitters

  • Orientable bracket to position a radar level transmitter at any angle up to a 45° angle
  • To direct the beam angle of the radar into the correct part of a tank, silo or stockpile
  • Material: stainless steel (1.4404 / 316L)
  • EPDM sleeve for increased grip of the radar

Low pressure flange disc

Low pressure flange disc

Process connection for OPTIWAVE level transmitters

  • Stainless steel disc to enable firm and even installation of level radars into onto tanks and silos
  • Suitable for radars with G1, G1½, G3, 1 NPT, 1½ NPT or 3 NPT process connections
  • Available in sizes DN50…DN200 / 2…8”
  • Low pressure conditions only: max. 1 barg at 20°C / 14.50 psig at +68° F

General information

Measurement principleRadar
Level measurement typeContinuous measurement
Measured mediaLiquids, Pastes, Slurries
Contact to measured mediumNo
Interface measurementNo
Measuring range (liquids)0…100 m/
0…328 ft
Process pressure-1…100 barg/
-14.5…1450 psig
Pressure ratingsEN (1092-1): PN100
ASME (B 16.5): Cl 1500#
JIS (B 2220): 10k
Process temperature-50…200°C/

Special version (on request):
Up to +700°C/+1292°F
Ambient temperature-40…+80°C/
Wetted partsAustenitic stainless steel (1.4404/316L), Polyetheretherketone (PEEK), Polytetrafluoroethylene (PTFE)
GasketsEthylene propylene diene monomer (EPDM), Fluoroelastomer rubber (FKM/FPM), Kalrez® 6375
Accuracy (liquids)±2 mm/
±0.08 in


Certificates/Approvals ExATEX, cQPSus, EAC Ex, IECEx, NEPSI
Certificates/Approvals SafetySIL 2/3
Certificates/Approvals MarineDNV
Certificates/Approvals OthersCRN / ASME B31.3, NACE, WHG
Ingress protectionIP66/68, NEMA4X/6P
NAMUR complianceNE 107, NE 21, NE 43, NE 53


Digital outputsFOUNDATION™ fieldbus, HART®, Profibus-PA
Analogue outputs4…20 mA

Process connections

Flange connectionsEN (1092-1): DN40…200
ASME (B 16.5): 1½…8″
JIS (B 2220): 40…200A
Thread connectionsMale:
1½ NPT