We are currently experiencing an issue with incorrect speed readings from our FMB120 devices connected to the Wialon server.
Since installing the FMB120 devices, we have been receiving frequent overspeed alerts whenever the reported vehicle speed exceeds 90 km/h. However, after verifying with the drivers, they confirmed that the vehicles were not travelling above 90 km/h at the time.
As a result, we are receiving false overspeed alerts, and the in-vehicle buzzer is also being triggered unnecessarily, causing inconvenience to the drivers.
Could you please advise if there are any configuration changes or recommended settings on either the FMB120 or the Wialon platform that could improve speed accuracy or prevent these false overspeed alerts?
Your advice and recommendations would be greatly appreciated.
Please note the overspeed alert criteria mentioned below. If you are receiving overspeed alerts in Wialon, it indicates that the device may have detected a speed exceeding the configured threshold. One more thing the speed is calculated via GNSS data.
Overspeed Event Trigger and End Criteria:
The overspeed event is triggered when the detected speed is greater than the configured maximum speed + 3% of the configured maximum speed.
The overspeed event ends when the detected speed falls below the configured maximum speed − 3% of the configured maximum speed.
To verify whether the alert is genuine or false, we recommend checking the vehicle’s data in Wialon for the 5–10 minutes preceding the event. Please verify:
Whether the vehicle was already in motion and gradually reached the overspeed threshold, or
Whether the device suddenly jumped from one location to another with a large GPS gap, which could indicate a false overspeed event caused by GPS inaccuracies.
Additionally, we recommend updating the device to the latest firmware using the link provided below to ensure the latest improvements and fixes are applied.
After checking with the truck owner, he informed me that another GPS tracking device from a different brand is also installed in the same truck. Surprisingly, we found that at the exact same date and time, the Teltonika FMB120 recorded a speed of 92 km/h, while the other GPS device recorded 71 km/h, which matches the driver’s claim.
Could you please help us understand why two GPS devices installed in the same vehicle would report significantly different speed readings at the exact same moment?
We would appreciate your advice on what could be causing this discrepancy and whether there are any settings or configurations on the FMB120 that we should verify.
