What is the purpose of this article?
This article demonstrates how to integrate multiple Rheonics sensors simultaneously in Ignition SCADA via MQTT. This is done by configuring Node-RED to read data from several SMEs and publishing them to MQTT topics so multiple Rheonics sensors (e.g., SRVs and SRDs) can be monitored in parallel. Ignition SCADA by Inductive Automation® subscribes to these topics, and allows the remote visualization of the parameters through the Rheonics templates in Ignition Designer.


To learn how to send Rheonics sensor data to an MQTT broker using Node-RED refer to Integrating Rheonics SME with Node-RED and MQTT for Remote Data Access


To learn how to connect Ignition SCADA to a MQTT broker to visualize Rheonics sensor data refer to Using Ignition SCADA to Visualize Rheonics SME Data via MQTT


1. Overview

In a real-world scenario, remote visualization of multiple sensor data is highly valuable for fluid monitoring and diagnostics across different locations. This section demonstrates how to connect and publish data from several Rheonics sensors through Node-RED, such as multiple SRVs and SRDs, through individual MQTT topics for each parameter. The following diagram presents the extended architecture used in this multiple sensor configuration.


Figure 1: Architecture with Multiple Sensors

Figure 1: Architecture with Multiple Sensors


2. Node-RED setup

To integrate various sensors, data is first obtained from each Rheonics SME via  Modbus TCP. In Node-RED, this is done by adding a new Modbus client for each SME, assigning each its respective IP address. In this example, parameters from three SRV sensors and one SRD sensor are read, each configured with its own IP. Each Modbus-Read node in Node-RED is paired with a corresponding MQTT-out node to publish the sensor data.


2.1. MQTT Topic Naming Convention

To keep topics organized, follow a structured naming scheme. Ensure each sensor’s data is published to a unique MQTT topic to prevent conflicts and to make data handling easier on the Ignition Designer side. For this example, the format used is the following:

  • SRV0

    • viscosity: srv0/viscosity

    • density: srv0/density

    • temperature: srv0/temperature

  • SRV1

    • viscosity: srv1/viscosity

    • density: srv1/density

    • temperature: srv1/temperature

  • SRV2

    • viscosity: srv2/viscosity

    • density: srv2/density

    • temperature: srv2/temperature

  • SRD

    • viscosity: srd/viscosity

    • density: srd/density

    • temperature: srd/temperature

    • kinviscosity: srd/kinviscosity


The final Node-RED flow looks as the following image:


Figure: Node-RED flow with multiple sensors

Figure 2: Node-RED flow with multiple sensors


3. Configuring Ignition SCADA MQTT

In Ignition SCADA, each SME can be linked to its custom namespace within the MQTT Engine module. This can help organize data by sensor and ensure clear identification across the interface.

  • Name: For this example, each sensor’s serial number was used as the namespace name and as the Root Tag Folder name.

  • Subscriptions: Assign the MQTT topics to each namespace based on the naming structure used in Node-RED.


This image displays the MQTT Engine’s configuration, showing how each sensor’s topics are grouped into their namespace. In this case, the serial name of the sensor was used for the Root Tag Folder, so it is easier to find the tags for each sensor.


Figure: Ignition MQTT Engine Configuration with Multiple Namespaces

Figure 3: Ignition MQTT Engine Configuration with Multiple Namespaces


4. Visualization in Ignition Designer

Using the Rheonics templates available on Ignition Exchange portal, sensor data can be easily visualized. For this example, the existing display template was modified to have more SRV displays available to correctly assign each display to its respective tag.


The following figure shows the Tag Browser in Ignition Designer, where the sensor values are grouped under each namespace created previously, corresponding to each SME.


Figure: Ignition Designer – Tag Browser with Folders of each Sensor

Figure 4: Ignition Designer – Tag Browser with Folders of each Sensor


After assigning each value correctly to each display, the final view in Ignition Designer looks like the following figure:


Figure: Rheonics Sensor Visualization on Ignition Designer

Figure 5: Rheonics Sensor Visualization on Ignition Designer



5. References