Radar (FMCW) level transmitter for powders and dusty atmospheres

  • Continuous, non-contact level measurement in high and narrow silos, hoppers or containers
  • 80 GHz radar, Lens antenna
  • Measuring range: 0…100 m / 328 ft
  • -50…+150°C / -58…+302°F; -1…40 barg / -14.5…580 psig
  • Icon/Logo for 80 GHz radar level measurement

OPTIWAVE 6500 – Version with Lens antenna and thread connection

Radar (FMCW) level transmitter OPTIWAVE 6500 – Version with Lens antenna and thread connection

The OPTIWAVE 6500 is a 2-wire 80 GHz radar (FMCW) level transmitter for demanding applications with powders in very dusty atmospheres. With its small beam angle, this radar is particularly suited for continuous, non-contact level measurement in high and narrow silos, hoppers or buffer storage containers up to 100 m / 328 ft. Due to the high signal dynamics of the FMCW radar, the level transmitter is ideal for low-reflective media, dust, uneven surfaces or tanks with obstacles. As it features a flush-mounted PEEK Lens antenna, there is no intrusion of the antenna into the tank.

The OPTIWAVE 6500 provides accurate and reliable readings in process conditions with temperatures up to +150°C / +302°F and pressures up to 40 barg / 580 psig. It offers flange or thread connections as well as an optional 112 mm / 4.4" antenna extension for the DN40 / 1.5”antenna. Approvals for use in hazardous areas are also available. The level transmitter comes with HART®7 communication.

Product highlights

  • 2-wire, loop-powered, with HART®7
  • Extremely high dynamics for clear vision despite dusty atmospheres or low reflective media
  • Empty tank spectrum function eliminates false reflections caused by tank internals
  • Flush-mounted PEEK Lens antenna (no tank intrusion):
    • DN70 / 2.75" (concave Lens) with 4° beam angle for distances up to 100 m / 328 ft
    • DN40 / 1.5" (convex Lens) with 8° beam angle for distances up to 30 m / 98 ft
  • 112 mm / 4.4" antenna extension for long nozzles
  • Unaffected by angle of repose – no need for antenna aiming kits
  • Antenna purging system for flange connection without antenna extension
  • ± 2 mm / 0.08” accuracy
  • 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
  • 3-year warranty

Typical applications


  • Level measurement in/on high and narrow silos with internal obstructions, buffer silos, bulk storage containers, hoppers

Minerals and mining industry

  • Fine powders (e.g. building materials)
  • Cement
  • Gypsum
  • Lime
  • Filler
  • Fly ash

Chemical industry

  • Plastic powder
  • Silica
  • Soap powder

Food and beverage industry

  • Milk powder
  • Coffee powder
  • Chocolate powder
  • Flour
  • Starch
  • Salt, sugar

Power industry, iron, steel and metal industry

  • Coal, coke

Pulp and paper industry

  • Saw dust

Case studies

Technical data

Measurement principlesRadar
Level measurement typeContinuous measurement
Measured mediaPowders, Solids
Contact to measured mediumNo
Interface measurementNo
Measuring range (solids)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
Ambient temperature-40…+80°C/
Wetted partsPolyetheretherketone (PEEK)
Process sealsEPDM, FKM/FPM, Kalrez® 6375
Accuracy (solids)±2 mm/
±0.08 in


Certificates/Approvals ExATEX, cQPSus, EAC, IECEx, NEPSI
Certificates/Approvals OthersCRN, NACE, WHG
Ingress protectionIP66/68, NEMA4X/6P


Digital outputsHART®
Analogue outputs4…20 mA

Process connections

Flange connectionsEN (1092-1): DN80…200
ASME (B 16.5): 2…8"
JIS (B 2220): 40…200A
Thread connectionsMale:
G1 1/2, G3
1 1/2 NPT, 3 NPT

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