Modbus is a serial communications communication protocol originally published by Modicon (now Schneider Electric) in 1979 for use with its programmable logic controllers (PLCs). Modbus has become a factory standard communication protocol and is now a commonly available means of connecting industrial electronic devices. The main reasons for the use of Modbus in the industrial environment are:

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Modbus enables communication among many devices connected to the same network, for example, a system that measures temperature and humidity and communicates the results to a computer.

Modbus protocol and Teltonika

Teltonika supports two types of modbus Protocol:

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The Modbus protocol module supports reading and writing to all valid Modbus registers from Modbus compatible devices.

Supported devices

Networks devices

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All Teltonika routers and gateways has ModBus TCP master functionality to read data from other slave devices;

As of 2020-03: Currently

• RUT955, TRB142 and TRB145 can be used to read data via ModBus RTU, since they has ModBus RTU master functionality;

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• RUT955, TRB142 and TRB145 can read ModBus slaves data using ModBus TCP and ModBus RTU protocols;

You can have more information in the link below:

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https://wiki.teltonika-networks.com/view/Monitoring_via_Modbus

Vehicles Telematics devices

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As of 2020-03, FMB640, FM63 and FMB125 support RS485, therefore they can support MODBUS Protocol, . But functionality it is not available, thus special development is required.