Tunnel – Control of the relays, digital outputs, digital inputs and 0-10V/4-20mA analog inputs of an MTX modem from a SCADA system using the MODBUS TCP protocol.

Scenario details:

• It is necessary to control 1 relay, 4 digital outputs (also connected to relays), 4 dry contact inputs and 2 analog inputs (one 0-10V type and another 4-20mA) located in a remote location
• Communication must be done from a SCADA system using Modbus TCP protocol
• For simplicity it is intended to use SIM cards with a public IP address
• The modem must be remotely configurable via SMS, Telnet and even Modbus

Solution: MTX-Tunnel firmware + MTX-IoT [4-S-N-N]-STD-P

Configuration example (config.txt file) for the indicated scenario:

Details:

• For simplicity, in this example the firewall has not been used, but remember that it has the FIREWALL_ parameters that could be used for greater communications security, allowing only communication with the Titan router from the public IP address of Scada.
• Remember that in the tables in Annex A of this manual you will find a table with the I / O of each modem model. Next to them you will find the modbus addresses of each one. For example, from the example model:

• If you want to activate / deactivate via GPbus a GPIO configured in the config.txt as output, you must write a “0” or a “1” in the associated modbus register (@Modbus)