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RSS-2-300W Surface Velocity Radar


Product Highlights

  • Contactless surface velocity measurement

  • Accuracy tested at Swiss Federal Institute of Metrology METAS and Brodarski Institut Labs

  • RS-232, RS-485 Modbus, analog 4-20 mA interfaces in all models

  • Remote configuration of all instrument parameters through any digital communication interface

  • Robust small size IP68 aluminum or stainless steel enclosure


  • Early flood warning

  • Monitoring of flow and irrigation channels

  • Accurate discharge monitoring in rivers

  • Flow tracking in salt and copper mine channels

  • Sewage and waste water discharge measurement


Product Description

The Geolux RSS-2-300W radar sensor uses radar technology for providing contactless measurement of surface flow velocity. Contactless radar technology enables quick and simple sensor installation above the water surface with minimum maintenance. The radar operates in K-band (24.075 GHz to 24.175 GHz) and provides flow speed readings 10 times per second over serial RS-232, RS-485 Modbus, and analog 4-20 mA output. The instrument is easily integrated with Geolux or third-party dataloggers and all of the settings can be remotely configured. An integrated MEMS sensor is used for automatic angle compensation. Internal vibration monitoring and SNR calculation can be used for measurement quality assessment.

Detailed Specifications

General specifications

Radar Type                                K-band 24.075 GHz to 24.175 GHz

                                                   Doppler radar, 20 dBm EIRP

Beam Angle                              12° Azimuth; 24° Elevation

Detection Distance                   20 m above the water

Speed Range                             0.02 m/s to 15 m/s

Resolution                                 0.001 m/s

Accuracy                                   1%

Sampling Frequency                10 sps

IP Rating                                   IP68


Serial Interface              1 x serial RS-485 half-duplex
                                       1 x serial RS-232 (two wire interface)

Serial Baud Rate           9600 bps to 115200 bps

Serial Protocols             GLX-NMEA, Modbus

Analog Output              1 x 4-20 mA

SDI-12 Interface            Available with optional add-on module

Connector                      M12 circular 12-pin

Electrical & Mechanical

Input Voltage                             9 to 27 VDC

Power Consumption                 950 mW operational, 85 mW standby

Maximal Current                      < 250 mA

Temperature Range                 -40 °C to +85 °C (without heating or

Device Outer Dimensions       110mm x 90mm x 50mm


EN 60950-1:2006+A1:2010+A11:2009+A12:2011+A2:2013
EN 62311:2008
EN 301 489-3 V2.1.1:2019
EN 301 489-1 V2.2.3:2019
EN 61000-6-2:2019
EN 61000-6-3:2021
EN 6100-6-2:2017
EN 300 440 V2.2.1:2018
EN 62368-1:2014+A11:2017
EN 62311:2008

EN 60529:2000+A1:2008+A2:2014 IP68

FCC Part 15 class B


Geolux holds two calibration certificates from the Federal Institute of Metrology (METAS), the Swiss national metrology institute. The Federal Institute of Metrology (METAS) serves as the federal center of competence for all measurement issues, equipment, and procedures. METAS stands at the cutting edge of measurement accuracy in Switzerland. It develops the national measurement base. That is to say, it looks after the physical implementation, mutual comparison, and thus the international recognition of measurement units. For this purpose, it operates the necessary laboratories and conducts the research and development needed.

cert 3.png

Mechanical Drawing

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