Guided radar (TDR) level transmitter for solids from granulates to powders

  • Continuous level measurement in buffer silos, bulk storage containers or hoppers
  • Insensitive to dusty atmosphere and deposit on the probe
  • Measuring range: 0.6…40 m / 2…131 ft 
  • -50…+200°C / -58…+392°F; -1…40 barg / -14.5…580 psig
  • Icon/Logo Security Integrity Level 2 (SIL 2)

OPTIFLEX 6200 C – Version with single cable

OPTIFLEX 6200 C Guided radar (TDR) level transmitter – Compact version with single cable

The OPTIFLEX 6200 is a 2-wire guided radar level transmitter based on the Time Domain Reflectometry (TDR) technology. It is designed for the level measurement of solids in bulk storage and other silos up to a height of 40 m / 131.2 ft. The single rod or single cable probes withstand high traction loads, making the level transmitter suitable for use in a wide range of applications with solids of different grain sizes – from fly ash and cement to gypsum and plastic granulates to tobacco and starch. This guided radar is equally suitable for applications involving milk, sugar, chocolate or coffee powder.

The OPTIFLEX 6200 is insensitive to dusty atmospheres or deposits on the probe. For applications that are difficult to access, a transmitter version with remote converter can be installed 100 m / 328 ft away from the probe. The converter comes with aluminium or stainless steel housing and is compatible with previous KROHNE TDR generations.

Product highlights

  • Designed to withstand high traction loads (<3.6 t)
  • Specific algorithm for low-reflective media
  • ESD protection (24 kV) for increased resistance to electrostatic discharges
  • Various converter and electronic versions to facilitate access to the device:
    • Available as compact version (C) or with remote converter (F) up to 100 m / 328 ft
    • Horizontal or vertical housing to suit every installation
  • Converter is rotatable and removable under process conditions and compatible with all process connections from previous KROHNE TDR models
  • Weather protection – protects the converter in extreme weather events
  • Stainless-steel housing for corrosive environment
  • SIL 2/3 (in preparation)
  • ±2 mm /±0.08" accuracy
  • Real-time clock for event logging
  • 3-year warranty

Typical applications


  • Level measurement of solids in buffer silos, bulk storage containers, hoppers etc.

Chemical industry

  • Plastic granulates (PPC, PVC, PE, LDPE, PP)
  • Soap powder

Food and beverage industry

  • Agri foods (tobacco, starch)
  • Milk powder, coffee powder, chocolate powder

Metals industry, minerals and mining industry

  • Hydrated lime, silica, gypsum, fly ash
  • Other fine powders (cement etc.)

Technical data

Measurement principlesGuided radar
Level measurement typeContinuous measurement
Measured mediaBulk solids, Granulates, Powders, Solids
Contact to measured mediumYes
Interface measurementNo
Probe diameter
  • Single cable Ø8 mm / 0.32"
  • Single rod Ø16 mm / 0.63"
Probe length0.6…40 m
1.97…131.23 ft
Measuring range (solids)0.6…40 m
1.97…131.23 ft
Process pressure (relative)-1…40 barg
-14.5… 580 psig
Process temperature-50…+200°C
Wetted partsAustenitic stainless steel (1.4404/316L), Polytetrafluoroethylene (PTFE)
Process sealsEthylene propylene diene monomer (EPDM), Fluorocarbon-based synthetic rubber (FKM/FPM), Kalrez® 6375, PEEK, Polytetrafluoroethylene (PTFE)
Accuracy (solids)±2 mm


Certificates/Approvals ExATEX, cQPSus, IECEx, INMETRO, NEPSI
Certificates/Approvals SafetySIL2
Certificates/Approvals OthersNACE
Ingress protectionIP66/68, NEMA4X/6P
NAMUR complianceNE 107, NE 21, NE 43, NE 53


Digital outputsHART®
Discrete outputsRelay
Analogue outputs4…20 mA

Process connections

Flange connectionsDN40…150
Thread connectionsMale:
1½ NPT