DISCLAIMER
The example below is intended to demonstrate one or more features or methods and is presented as a configuration example only. Schneider Electric assumes no liability for the use or application of this example or any portion thereof.
This document is meant to be a simple guide on how to test the Geo SCADA MQTT driver JSON Schema A. A detailed description on how this driver works can be found in the manual. The MQTT driver must connect to a Broker and, for this article, we are going to use the open source Mosquitto MQTT Broker. There will be no instructions on how to install Mosquitto and no comments on its features. Also note that Schneider Electric has no responsibility on the use of the Mosquitto Broker.
We will start the Mosquitto Broker, which will run on the same machine as Geo SCADA, from a command prompt dialog box (running as Administrator):
The broker will be listening on port 1883. Leave the command prompt window open.
With the broker running, let's configure the Geo SCADA objects, within ViewX.
We will create:
- A MQTT Broker object;
- A MQTT > JSON Schema A > Device
- A MQTT > JSON Schema A > Analog Point
Below the minimum configuration for the Broker object:
After saving the configuration, we can check that the connection to the Mosquitto Broker was established by taking a look at the command prompt window:
Back to ViewX, let's configure the Device (note that we are subscribing to a Topic called "test"):
Once we save the configuration, we can see, from the Mosquitto Broker window, that the subscription was accepted:
Now, let's configure the Analog point (we will read "value1"):
Now we are going to run "moquitto_pub" tool on another command prompt window to publish time and value for the tag "value1". More details on the JSON Schema A message format can be found in the Geo SCADA manual.
Please note that the time stamp is in the UNIX Epoch time in seconds (UTC), remember to change it when replicating this example:
Below the results on a mimic:
Note: The MQTT driver log file is a good start in case troubleshooting is needed. It can show, for example, if the message received could not be parsed properly.
