Heltec HRI-4853

Overview

The Heltec HRI-4853 is an industrial-grade Data Transfer Unit (DTU) that bridges RS-485 serial devices to IP networks via Ethernet or LTE. Built around the ESP32-D0WDQ6 dual-core MCU, it converts Modbus RTU data from RS-485 sensors and actuators into TCP, UDP, or MQTT packets, enabling remote monitoring and control of industrial equipment over standard network infrastructure.

The device features a wide 4.5-28V DC power input, an industrial operating temperature range of -40 to +85 degrees Celsius, and a DIN-rail compatible enclosure rated IP65. Configuration is handled through a built-in web interface accessible over WiFi at 192.168.4.1 — no external software is required. The RS-485 interface supports baud rates from 1200 to 115200 bps with a 1024-byte buffer and up to 240-byte single packets.

Thanks to its ESP32 foundation and the MAX3485 RS-485 transceiver, the HRI-4853 can be flashed with ESPHome firmware for deep integration with Home Assistant. The ESPHome configuration exposes Modbus sensor readings directly as Home Assistant entities, making it an excellent bridge between legacy industrial sensors (temperature, humidity, energy meters) and modern smart home or building automation systems. An RTL8201 Ethernet PHY provides reliable 10/100 Mbps wired connectivity for always-on deployments.