Radar (FMCW) level transmitter for liquids in narrow tanks with internal obstructions

  • Continuous, non-contact level measurement in small or large tanks with agitators as well as long nozzles
  • 80 GHz radar, flush-mounted Lens antenna
  • Measuring range: 0…100 m / 328 ft/li>
  • -50…+150°C / -58…+302°F; -1…40 barg / -14.5…580 psig
  • Icon/Logo for 80 GHz radar level measurement

OPTIWAVE 7500 – Version wth Lens antenna and thread connection

Radar (FMCW) level transmitter OPTIWAVE 7500 – Version wth Lens antenna and thread connection

The OPTIWAVE 7500 is a 2-wire 80 GHz radar (FMCW) level transmitter for demanding liquid applications involving narrow tanks with long nozzles and internal obstructions like agitators or heating coils. Its very small beam angle and negligible dead zone make this FMCW radar the optimal choice for continuous, non-contact level measurement in both extremely small and very high tanks (up to 100 m / 328 ft). The level transmitter is even able to measure through tank roofs made of non-conductive materials. Its PEEK Lens antenna is insensitive to deposits and well suited for corrosive environments. As the antenna is flush-mounted, there is no intrusion into the tank.

The OPTIWAVE 7500 provides accurate readings even in processes with fast changing levels. It can be used in operating temperatures of up to +150°C / +302°F and pressures up to 40 barg / 580 psig. This level transmitter offers a wide range of flange connections and thread connections (starting from 3⁄4"). It comes with approvals for use in hazardous areas as well as extensive device diagnostics (acc. to NE 107) and HART®7 communication.

Product highlights

  • 2-wire, loop-powered, with HART®7
  • Small beam angle (4° with DN70 / 6” Lens antenna)
  • PEEK flange protection against corrosive media 112 mm / 4.4" antenna extension for long nozzle
  • Empty tank spectrum function eliminates false reflections caused by tank internals
  • ± 2 mm / 0.08” accuracy
  • Can measure in processes with fast changing levels (≤60 m/min or 196.85 ft/min)
  • Wide range of flange or thread connections
  • Large, backlit LCD screen with 4-button keypad for operation with bar magnet; no need to open the housing cover
  • PACTware™, HART® DDs and DTMs provided free of charge with full functionality
  • Extensive sensor and process diagnostics (incl. NE 107)
  • 3-year warranty

Typical applications


  • Level measurement in/on small and narrow tanks with internal obstructions (e.g. heating coils, agitators etc.)
  • Level meausrement in tanks with long nozzles
  • Processes with fast changing levels (≤60 m/min / 196.85 ft/min)
  • High accuracy applications where ±2 mm / 0.08¨ is specified

Chemical industry

  • Solvents, acids
  • Foaming agents
  • Urea
  • Chlorine
  • Resins
  • Paint, ink
  • Corrosion inhibitors

Petrochemical industry, oil and gas industry

  • Liquefied Petroleum gas (LPG)
  • Hydrocarbons and fuels
  • Slop oil
  • Drilling mud
  • Ethylene
  • lubricant oil

Power industry

  • Hydrocarbons
  • Lime milk

Accessories for this product

OPTICHECK Master Verification tool


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)
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
Purge port connection with G1 1/2 thread

Purge port connection

Purging system for OPTIWAVE level transmitters 

  • Special purge kit thread with holes
  • For compressed air or water cleaning of level radar antennas
  • Suitable for radars with G1½, G3, 1½ NPT and 3 NPT process connections
  • Can be additionally equipped with an antenna aiming kit
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


Technical data

Measurement principlesRadar
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 (relative)-1…40 barg/
-14.5…580 psig
Pressure ratingsEN (1092-1): PN40
ASME (B 16.5): Cl 300#
JIS (B 2220): 10k
Process temperature-50…+150°C/
Wetted partsPolyetheretherketone (PEEK)
Process sealsEPDM, FKM/FPM, Kalrez® 6375
Accuracy (liquids)±2 mm/
±0.08 in


Certificates/Approvals ExATEX, cQPSus, EAC, IECEx, NEPSI
Certificates/Approvals OthersCRN, NACE, WHG
NAMUR complianceNE 107, NE 21, NE 43, NE 53


Digital outputsHART®
Analogue outputs4…20 mA

Process connections

Flange connectionsEN (1092-1): DN50…200
ASME (B 16.5): 2…8"
Thread connectionsMale:
G¾, G1, G1 ½, G3
¾ NPT, 1 NPT, 1 ½ NPT, 3 NPT