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OTT RLS Radar Water Level Sensor

OTT RLS Radar Water Level Sensor


The OTT RLS, non-contact radar level sensor with pulse radar technology is ideal for monitoring in remote or hard to reach locations.


  • Transmit & receive antenna enclosed in a lightweight, durable housing with flat antenna design
  • Easily mounts to a bridge, frame, pipeline, or extension arm
  • Connects to NexSens iSIC data logging system via SDI-12 interface
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Why Buy From Fondriest?


The RLS non-contact radar level sensor with pulse radar technology is ideal for monitoring in remote areas and applications where conventional measuring systems are not suitable. The RLS accurately and efficiently measures surface water level With a non-contact distance range of up to 115 feet above water. The sensor is IP67 waterproof and has extremely low power consumption, making it ideal for solar-charged monitoring systems.

The radar level sensor uses a revolutionary level measurement technology, meeting the USGS accuracy requirement of +/-0.01 feet. Two antennas are enclosed in a compact housing and transmit pulses toward the water surface. The time delay from transmission to receipt is proportional to the distance between sensor and water surface. A sampling rate of 16 Hz (16 measurements/second) with 20 second averaging minimizes water surface conditions such as waves and turbulence. The RLS does not require calibration and is unaffected by air temperature, humidity, flood events, floating debris, or contaminated water.

What's Included:
  • (1) Radar level sensor
  • (1) 2-part swivel mount
  • (1) Installation kit - Includes (4) 6x40mm wood screws & (4) plastic plugs
  • (2) Double open-ended wrenches (10x13)
  • (1) Factory acceptance test certificate (FAT)
  • (1) Operations manual
Image Part # Product Description Price Stock Order
OTT RLS Radar Water Level Sensor RLS radar water level sensor, FCC Version (25 GHz), SDI-12 & 4-20mA output Drop ships from manufacturer
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Questions & Answers

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Where should I place my Radar Water Level Sensor?
In order to obtain reliable and correct measurements, you should avoid submerged obstructions and there should be a clear path between the sensor and the water to avoid false reflections. There is a full list of helpful site selection tips under the Documents Tab.
What maintenance do I need to preform to keep my Radar Water Level Sensor clean?
The OTT RLS sensor does not require calibration and there are no parts that need regular replacing. To maintain your sensor be sure to: check for dirt, obstructions in the measurement beam, and plausibility of the measured values. To clean your sensor, use commercial, gentle and non-erasing cleaners with a soft sponge.
My sensor is not responding to the SDI-12 Interface, what should I check?
There are a few possibilities when having trouble with the SDI-12 interface. First, check the fuse in the power supply. If that is working, the power supply may be too low or too high. You should be using 12/24V. If your voltage is correct, make sure you are using DC (direct current).

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