node-red-contrib-micro800plc

A Node-RED custom node package for connecting to Allen-Bradley Micro800 PLCs using Node-Logix. This package provides two nodes: Micro800 (for single tag read/write) and Micro800-Array (for array tag read/write), making it easy to integrate your PLCs with Node-RED flows.

---

Features

• Configure PLC connection parameters
• Read and write single tags or arrays of tags on Allen-Bradley Micro800 PLCs
• Supports both simple and advanced use cases
• Built on top of the Node-Logix library

---

Nodes

Micro800

Read or write a single tag on a Micro800 PLC.

Configuration:

• Host IP: The IP address of the PLC
• Read Tag: The tag to read
• Write Tag: The tag to write
• Write Value: The value to write (for write action)
• Action: Choose "Read" or "Write"

Input Message Format:

• To override configuration, set properties in msg.payload:
  • action: "read" or "write"
  • tag: Tag to use (overrides configured tag)
  • value: Value to write (for write action)

Examples:

{
  "payload": {
    "action": "read",
    "tag": "MyTag"
  }
}

{
  "payload": {
    "action": "write",
    "tag": "MyTag",
    "value": 123
  }
}

---

Micro800-Array

Read or write an array tag on a Micro800 PLC.

Configuration:

• Host IP: The IP address of the PLC
• Array Tag: The name of the array tag (e.g., MyArrayTag)
• Data Type: The data type of the array elements (DINT, INT, REAL, BOOL, etc.)
• Array Length: Number of elements to read or write
• Action: Choose "Read" or "Write"
• Write Value: The array of values to write (for write action)

Input Message Format:

• To override configuration, set properties in msg.payload:
  • action: "read" or "write"
  • arrayTag: Tag to use (overrides configured tag)
  • dataType: Data type (overrides configured type)
  • length: Number of elements (overrides configured length)
  • writeValue: Array of values to write (for write action)

Examples: Read 5 elements from an array:

{
  "payload": {
    "action": "read",
    "arrayTag": "MyArrayTag",
    "dataType": "DINT",
    "length": 5
  }
}

Write an array to the PLC:

{
  "payload": {
    "action": "write",
    "arrayTag": "MyArrayTag",
    "dataType": "DINT",
    "length": 3,
    "writeValue": [10, 20, 30]
  }
}

...

...

...

...

---

---

Installation

1. Install this node in your Node-RED user directory:

   npm install node-red-contrib-micro800plc

2. Restart Node-RED.
3. Drag the Micro800 or Micro800-Array node into your flow.
4. Configure the PLC connection and tag parameters in the node properties.

---

Output

Both nodes output a message with the following structure in msg.payload:

• tag or arrayTag: The tag name used
• value: The value(s) read or written
• dataType: The data type used
• status: Operation status (e.g., read-success, write-success)

---

License

MIT