The Cheap Modbus to MQTT Converter You Didn't Know Existed

If you have Modbus RS485 devices like solar inverters or industrial sensors, getting them into Home Assistant or Node-RED can be a massive headache. In this video, we look at an incredibly powerful, compact, and affordable protocol decoder that bridges Modbus RTU/TCP directly to MQTT JSON! We walk step-by-step through setting up this budget-friendly gateway using its advanced Windows configuration tool. You'll learn how to establish a bi-directional connection: converting sensor data (like temperature and humidity holding registers) into clean MQTT JSON payloads, and sending MQTT commands back to control physical Modbus coil outputs. Whether you're integrating a solar inverter, a custom sensor array, or PLC components into your smart home, this tiny device is an absolute game-changer for IoT enthusiasts and DIYers alike! 🔑 Key Takeaways Dual Functionality: How to configure the device as both a standard Modbus RTU to Modbus TCP server and an active MQTT client. Bi-Directional Communication: Step-by-step guide to reading holding registers (sensors) into JSON payloads and writing to coils (relays) via incoming MQTT strings. Network Optimization: How to use the "Transmit on Change" feature so you don't flood your MQTT broker with duplicate data. Advanced JSON Structuring: A brief look at the extensive documentation for setting up nested structures, arrays, and offline monitoring. ● Viewers' Discount (5% off): CSONGOR5 ● Affiliate Link: https://shop.valtoris.com/shop/1-port... If you like what I do here, you can support me with Youtube Thanks, or Memberships: One time donation via PayPal: https://paypal.me/trainsmoney?country... Join this channel to get access to perks:    / @csongorvarga   TikTok channel most on trains, big and small:   / frontendfriday   And same in Instagram:   / hamptongardenrailway   Chapters: 0:00 Intro 4:11 Chapters 4:27 Config App 6:09 RS485 to TCP 10:00 Setup for MQTT 11:11 MQTT read config 13:25 JSON read setup 21:12 Only transmit changes 24:49 Sending data 29:26 Summary 31:45 Outro