Flow Sensors

KDA Doppler Wedge Sensor

Part No. KDA-K/KDS-K

Wedge-shaped flow velocity sensor for channels

Ultrasonic sensors for flow measurement in slight to heavily polluted media. Wedge shape for installation on channel wall or channel bottom

  • Latest fourth-generation intelligent <link https: www.nivus.com en service-download know-how doppler external-link-new-window>Doppler technology
  • Cost-effective pricing
  • Suitable for all channel cross sections
  • Easy to install without the need for additional constructions
  • Cables can be extended without any problems
  • Measurement in heavily polluted and abrasive media
  • Built-in pressure cell mechanically protected


KDA flow velocity sensors are suitable for continuous measurement of slight to heavily polluted media. The wedge-shaped sensors are designed for installation on either the channel wall or the channel bottom.

Combined with transmitter types such as PCM F and OCM F the result is a complete flow measurement system.

Typical applications for KDA wedge sensors

  • Wastewater treatment plants: intake, discharge, activated sludge tank intakes, return sludge, recirculation, surplus sludge, digester discharge and flocculant dosage
  • Permanent measurements on stormwater treatment facilities such as stormwater overflow tanks, rainwater sedimentation and retention tanks
  • Direct discharge control, infiltration (extraneous water) or leakage detection
  • Industrial wastewater networks
  • Measurement campaigns in channel networks
  • and many more






Measurement principle Doppler (flow velocity)
Piezo-resistive pressure measurement (level measurement)
Sensor types v-sensor with T-compensation

v-sensor with T-compensation and h measurement (hydrostatic)
Protection IP 68
Ex-Approval II 2G Ex ib IIB T4 (ATEX)
Ex ib IIB T4 Gb (IECEX)
Operating temperature -20 °C to +50 °C
-20 °C to +40 °C if using the sensors in Ex Zone 1
Storage temperature -30 °C to +70 °C
Operating pressure max. 4 bar (combi sensor with pressure cell max. 1 bar)
Cable lengths 10/15/20/30/50/100 m pre-configured, can be extended upon request;
a pressure compensation element is required if cables longer than 30 m are used with sensors featuring an integrated pressure measurement cell. The compensation element can be used also to connect the extension.
Cable types Combi sensor with pressure measurement:: LiYC11Y 2x1.5 + 1 x 2 x 0.34 + PA 1.5/2.5
Sensors without pressure measurement: LiYC11Y 2 x 1.5 + 1 x 2 x 0.34
Outside cable diameter Combi sensor with pressure measurement: 9.75 mm ±0.25 mm
Sensors without pressure measurement: 8.4 mm ±0.25 mm
Sensor connection Cable end pre-configured for connection to OCM F / FR,
cable types "K" or "L"
Medium-contacting materials PVDF (wedge sensor body); stainless steel 1.4571 (ground plate); Polyurethane (cable sheath, screw joint and pipe sensor head)
Additionally for sensors with pressure measurement cell: Hastelloy© C276 (pressure cell); Viton; PA/PR (pressure cell gasket)
Optional: cable with FEP coating (sensors without pressure measurement only)
Flow velocity measurement
Measurement range -600 cm/s to +600 cm/s
Measurement uncertainty ±1 % of measurement range end value
Zero point drift absolutely stable zero point
Beam angle ±5 degrees
Level measurement – Pressure
Measurement range 0 to 5 m
Zero point drift max. 0.75 % of final value (0 – 50 °C)
Measurement uncertainty standing medium:
+/- 0.5 of final value
Temperature measurement
Measurement range -20 °C to +60 °C
Measurement uncertainty ±0.5 K

Specifications subject to change.

Datasheet KDA Sensors

Datasheet for KDA pipe and wedge sensors

Technical Instruction for Doppler Sensors

Technical Instruction for KDA Doppler sensors (pipe and wedge style)

EC Type Examination Certificate EX KDO

Declaration of Conformity Compact Doppler Active Sensors

Kompaktdoppler-AktivsensorenKDA-K.../ KDA-R.../ KDS-K…/ KDS-R…

EC-Type Examination Certificate KDA-K, KDA-R

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