Negative input (Ground Sense) on Teltonika trackers

Connecting a negative input to a GPS Tracker is a great way to detect when a negative pulse has been retrieved from your GPS Tracker. Negative input (ground sense) purpose is to detect ground when it‘s connected, and this allows much easier and safer installation of external accessories. There won‘t be needed to connect a power supply to external accessories that digital input could sense a change of a signal.

The animated picture below shows a simple example of a negative input usage scenario. There are many alarm buttons, sensors and other accessories that operate on this principle: one alarm button pin is connected to the ground (it could be connected to any ground, not necessarily to FMB140 device ground), other pin – to negative input. When the button is pressed, ground is connected and negative input detects it.

Dont forget to change the Codec on your Teltonika GPS Tracker to Codec 8 Extended!