Modbus Output Node

Modbus Output Node

The Modbus node sends data to remote PLCs via the Modbus protocol over an IP connection. The Modbus node will send data to designated field addresses for the specified device. This node does not output data to the flow.

Modbus is a commonly available means of connecting industrial electronic devices in industrial environments. It uses character serial communication lines, Ethernet, or the IP suite as a transport layer. Modbus supports communication between multiple devices connected to the same cable or network and is often used to connect a plant supervisory computer with a remote terminal unit (RTU) in supervisory control and data acquisition (SCADA) systems.

A single physical output is called a coil; a single physical input is called a discrete input or a contact. The data types are:

Only coils and holding registers can receive input. Coils are limited to 1 bit, and holding registers to 16 bits.

Adding a Modbus Output node to your workflow

1. First, select your desired solution and navigate to Rayven Workflow.
2. Select ‘Outputs’ from the left-hand panel.
3. Find the Modbus Output node and drag it onto the canvas.
4. Double click on the Modbus Output node to open its configuration window.

Configuring your Modbus Output node

1. First, give your node a Name. Choose something simple that clearly explains its purpose.
2. Enter the destination IP Address of the Modbus device.
3. Enter the Port for the Modbus PLC. Note that the node defaults to 502 (the Modbus default port).
4. Under Field Name, enter the JSON Field that will be the data source.
5. Enter the Modbus Field Type (e.g., Holding Register).
6. Enter the Modbus Field Address (e.g., 400001). Since Modbus has a field size limited to 1 bit or 16 bits, flow variables must first be transformed to the appropriate data type and may need to be sent to multiple addresses.
7. You must identify at least one Modbus register to write to and can add additional objects using the '⊕ Add Value' button.

Once you have configured your Modbus Output node, click Activate and then Save. It is now ready to receive data from the workflow.