Why does the 1.5-inch 80G radar show zeros or spike values in historical data?

Model: JJY-YLD128HS-1.5 — 1.5-inch 80 GHz radar level transmitter

Symptom

During commissioning the live readings were normal, but the historical data contained zeros. Also, when the actual level was 0.5 m, occasional readings of several metres appeared. Filtering and echo learning did not stop the fluctuation; changing the blind zone and switching to a nearby frequency band also failed.

Fix

Replace the YCD8S unit with the YLD8S and upgrade to the latest firmware (2025-12-17 build). After the swap the jumps stopped and no further fluctuation was reported.

To prevent sudden jumps, set the sliding-window averaging to 10 / 30 / 60 — a larger window smooths out spikes.

Related reading

• 80GHz Radar Level Sensor Troubleshooting Guide: Echo & Signal Diagnosis
• Why does the 80G radar with display report within blind zone?
• Why does the liquid level display Insufficient Echo Energy?
• Why does the radar water level measurement lag and respond slowly?

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