Industry: water conservancy Application: river channel water level Device: radar level transmitter Firmware: 20260602 Symptom: false 0.07 m reading
The problem
Site & symptom
A radar level transmitter was installed over a river channel for continuous water level monitoring. At the site the customer reported that the unit was measuring an inaccurate level of 0.07 m, and the value did not follow the real water surface.
Root cause
The measurement point is an open river channel, so the water surface never rises up to the transducer. Instead of the water, the transmitter was locking onto an unwanted echo right in front of the antenna. Because the blind zone was still small, the unit accepted that near-range echo as the level – which is why the reading stayed fixed at 0.07 m instead of tracking the water.
The installation
Field case 1 – the radar level transmitter installed above the river channel.
Field case 1 – second view of the installation.
How we fixed it
Solution
After talking through the application we confirmed that the water would never reach the transducer, and asked the customer to make three changes: (1) switch the transmitter to suspended installation, (2) enlarge the blind zone to 0.3 m so everything immediately in front of the antenna is ignored, and (3) select the real target and run false-echo learning, which stores the unwanted echo so it is no longer treated as the level.
Result
After the adjustment the transmitter detected the correct waveform and delivered accurate level data.
Echo spectrum: before and after
Before – the echo spectrum behind the false 0.07 m reading.
After – a correct waveform and an accurate level.
What this case teaches
On an open site such as a river channel the water surface may never reach the transducer – never assume the strongest echo is the medium you want to measure.
A blind zone that is too small lets the transmitter lock onto reflections right in front of the antenna.
Suspended installation plus false-echo learning removes a fixed, near-range echo for good.
Measuring level over a river, channel or open water? Tell us the range, the mounting and the medium – we will recommend the right radar level transmitter and the correct blind-zone setting.
