Uni Directional BACnet IP to MQTT Publisher for Single Device (JSON Payload)

Last Code Revision Date: 03-Sep-2025

BACnet to MQTT Single Device

This project bridges BACnet devices to MQTT, allowing BACnet data to be published to an MQTT broker for integration with other systems.

Features

• Connects to a BACnet device over IP
• Reads multiple BACnet properties (customizable via config)
• Publishes BACnet data to a specified MQTT topic
• Configurable BACnet tags and MQTT broker details in config.json
• Handles BACnet and MQTT connection errors gracefully
• Simple, single-device focus for easy integration

Configuration

Edit the config.json file to set:

• BACnet device IP and tags to read
• MQTT broker hostname, port, topic, and retry interval
• Polling interval for BACnet reads

Example config.json:

{
   "bacnet": {
      "deviceIp": "192.168.1.19",
      "tags": [
         { "objectType": 0, "objectInstance": 0, "name": "Indoor Temperature" },
         { "objectType": 0, "objectInstance": 1, "name": "Glycol Water Temperature" }
      ]
   },
   "mqtt": {
      "hostname": "127.0.0.1",
      "port": 1883,
      "topic": "bacnet_data",
      "retryInterval": 5000
   },
   "interval": 1000
}

Usage

1. Install dependencies:

    npm install
   

2. Start the application:

    node index.js
   

3. The app will read BACnet values at the configured interval and publish to MQTT.

Project Structure

• index.js – Main application logic
• config.json – Configuration for BACnet and MQTT
• package.json – Project metadata and dependencies

Troubleshooting

• Ensure BACnet device is reachable from your network
• Check MQTT broker is running and accessible
• Review console logs for connection or data errors