Excessive ignition ON/OFF events on Teltonika FMB920 – How to filter or debounce signals

Jeruso 2 months ago

Good morning,

I am experiencing an issue with a Teltonika FMB920 device: it sends an excessive number of ignition ON/OFF notifications. I have configured the Teltonika ignition detection to a voltage range of 13.5–18 V. If the voltage is within this range, ignition is considered ON; if it falls outside, ignition is OFF.

However, the server logs show very rapid ON/OFF events, sometimes just a few seconds apart. Example:

2025-11-27 00:24:32 INFO: Event id: 353742371XXXXXX, time: 2025-11-27 00:24:24, type: ignitionOn, notifications: 1
2025-11-27 00:24:32 INFO: Event id: 353742371XXXXXX, time: 2025-11-27 00:24:26, type: ignitionOff, notifications: 0

And part of the ON/OFF event report:

27/11/2025, 00:15:11 Ignition ON
27/11/2025, 00:15:12 Ignition OFF
27/11/2025, 00:17:00 Ignition ON
27/11/2025, 00:17:06 Ignition OFF
27/11/2025, 00:17:09 Ignition ON
27/11/2025, 00:17:12 Ignition OFF

This “bouncing” causes many unnecessary events. I am looking for a solution that correctly reflects when the vehicle starts and stops, without creating multiple rapid events. Possible approaches I am considering:

Server-side filtering: Implement a minimum time threshold (e.g., only generate ignition events if the ignition state remains stable for X seconds).

Calculated attribute: Create a derived attribute for this device that smooths the ignition signal and only triggers ON/OFF when the state change is persistent.

Device configuration: Check if the FMB920 supports a built-in debounce or delay for ignition detection to prevent short voltage spikes from generating events.

I would like advice on the best method to implement this so that the events are accurate and reliable.

Anton Tananaev 2 months ago

If Teltonika supports built-in debounce, that would be the best option because it can sample the data much more frequently.

sem13 22 days ago

Здравствуйте. Меня конечно трудно назвать специалистом по серверу. Но так как вы видите все сообщения о зажигании, то это означает что прибор присылает множество не нужный сообщений, а это лишняя нагрузка на сеть и сервер.
Значит будет более правильным убрать дребезг контактов на самом устройстве. Вариант 1 в настройках прибора такая функция есть, сам делал.
2 вариант поставить между входом зажигания, минусом или плюсом, в зависимости типа подключения, конденсатор 3000 микрафорат 50 вольт.