HD67C05-2-G43-B2 Industrial Modbus Slave and MQTT Broker Converter with LAN and LTE

HD67C05-2-G43-B2 – Industrial Modbus Slave and MQTT Broker Converter with LAN and LTE.

The HD67C05-2-G43-B2 is a robust industrial communication converter that bridges Modbus RTU in Slave mode with modern MQTT architectures, enabling seamless data exchange between traditional automation networks and IoT or cloud-based systems. The G43 variant adds LTE connectivity with a SIM card, making the device ideal for remote sites, distributed installations and applications requiring mobile communication.

Download software (SW67C05):
Click here to download the configuration software

According to the device manual (section “Characteristics”), the unit provides a wide operating temperature range of -40°C to +85°C, flexible 8…24 V AC / 12…35 V DC power supply, electrical isolation between Ethernet and the power stage, and DIN rail mounting for industrial environments.

Key Features and Advantages

• Modbus Slave RS485 – exposes MQTT data as Modbus registers, as detailed in the “Modbus Map” section of the manual.
• Built-in MQTT Broker – supports publish/subscribe communication, JSON payloads, QoS management and user authentication.
• LAN 10/100 Mbps – reliable wired connectivity with autosensing.
• LTE with SIM card – as described in the “Mobile” section: SMA Female antenna connector, Micro-SIM slot and full APN configuration support.
• Galvanic isolation for increased network safety between Ethernet and power supply.
• SW67C05 software – full configuration of Modbus, MQTT, topics, network and security settings.
• Diagnostic LEDs – status indicators for RS485 activity, errors and network state described in the “LEDs” section.
• Recovery Mode – allows restoring configuration in case of firmware issues.

How the Converter Works

Operating as a Modbus Slave, the device maps MQTT data into Modbus registers, allowing legacy automation systems to access IoT-driven information without modifying existing infrastructure. Register mapping follows the structure presented in the manual’s Modbus table, including support for Holding Registers, Input Registers and optional bit-level interpretation.

Simultaneously, the HD67C05-2-G43-B2 acts as an MQTT Broker, enabling communication between MQTT clients, managing topics, handling subscriptions and publishing updates from RS485 or external MQTT sources. The device can also synchronize messages between MQTT and Modbus registers for two-way data exchange.

Ports and Connectivity

• 1× RS485 Modbus Slave – 3-way screw terminal (5 mm).
• 1× Ethernet RJ45 – 10/100 Base-T autosensing.
• 1× SIM slot – for LTE mobile connectivity.
• 2-pin screw power connector – 5 mm pitch.

Technical Specifications

• Modbus Slave speed: up to 115200 bps
• MQTT Ethernet: 10/100 Base-T autosensing
• LTE SIM: Micro-SIM, SMA antenna connector
• Power supply: 8…24 V AC or 12…35 V DC
• Operating temperature: -40°C to +85°C
• Dimensions: 70 × 60 × 95 mm
• Weight: approx. 200 g
• Mounting: DIN rail 35 mm
• Software: SW67C05
• Order code: HD67C05-2-G43-B2

Applications

• Integration of Modbus devices with IoT platforms via MQTT.
• Remote monitoring and industrial telemetry.
• HVAC/BMS automation systems.
• Energy monitoring and photovoltaic installations.
• Distributed field infrastructure using LTE communication.

The HD67C05-2-G43-B2 is a reliable, flexible and secure industrial converter that seamlessly connects Modbus Slave devices with MQTT-based platforms. With LTE support, wide temperature tolerance and robust electrical isolation, it is an excellent choice for remote, energy, HVAC and industrial automation applications requiring dependable communication.