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

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

The HD67C05-2-G43-VPN-B2 is a professional industrial converter designed to integrate Modbus RTU in Slave mode with modern MQTT communication architectures. This model includes a built-in VPN service, ensuring secure, encrypted data transmission between remote industrial sites, SCADA servers and IoT platforms. With Ethernet connectivity and LTE support via a SIM card, this converter is ideal for distributed systems requiring reliable, redundant communication links.

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

The technical documentation highlights an extended operating temperature range from -40°C to +85°C, electrical isolation between the Ethernet port and the power supply, and flexible 8…24 V AC / 12…35 V DC power input, making the device highly suitable for harsh industrial environments.

Key Features and Advantages

• Modbus Slave RS485 – provides MQTT data in the form of Modbus registers, following the internal register mapping structure.
• Integrated MQTT Broker – supports JSON and RAW payloads, QoS, client authentication, subscription management, cyclic publishing and MQTT Bridge for external broker integration.
• VPN Support – enables secure tunnels for encrypted communication, ensuring safe remote access to industrial devices and critical infrastructure.
• LAN + LTE connectivity – Ethernet port with autosensing and LTE communication via SIM card, including SMA antenna support and APN configuration, allowing operation in mobile or remote environments.
• Galvanic isolation between Ethernet and the power section increases resilience and electrical safety.
• SW67C05 software – used for configuration of Modbus, MQTT topics, network parameters and VPN settings.
• Diagnostic LEDs – provide visual feedback for RS485 communication, network activity, status and error conditions, as documented in the LED table.
• Recovery Mode – allows full device recovery in case of failed firmware updates.

How the Converter Works

As a Modbus Slave, the HD67C05-2-G43-VPN-B2 makes data received from MQTT topics available to RS485 masters (PLCs, SCADA controllers, BMS units). The converter maps MQTT payloads into Holding or Input registers, allowing traditional industrial systems to seamlessly access IoT-derived or cloud-originated information.

Simultaneously, the device operates as an MQTT Broker, managing publish/subscribe communication, relaying data between RS485 and MQTT and enabling two-way synchronization of industrial datapoints. The integrated VPN service provides encrypted remote access, essential for distributed automation systems, energy installations and mission-critical telemetry.

Ports and Connectivity

• 1× RS485 Modbus Slave – 3-way screw terminal (5 mm pitch).
• 1× Ethernet RJ45 – 10/100 Mbps autosensing.
• 1× SIM slot – LTE mobile data communication.
• 2-pin power connector – screw-type, 5 mm pitch.

Technical Specifications

• Modbus Slave speed: up to 115200 bps
• MQTT over Ethernet: 10/100 Base-T autosensing
• LTE SIM: SMA antenna connector, Micro-SIM support
• 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-VPN-B2

Applications

• MQTT-based IoT infrastructures.
• Remote monitoring and industrial telemetry.
• Energy sector, PV installations and distributed substations.
• HVAC, BMS and building automation.
• Secure cloud integration requiring VPN protection.
• RS485 device integration with remote or LTE-based networks.

The HD67C05-2-G43-VPN-B2 is a secure, versatile and robust industrial converter that seamlessly connects Modbus Slave networks with MQTT infrastructures. With integrated VPN, LTE connectivity, wide environmental tolerance and comprehensive diagnostics, it is an excellent solution for industrial IoT, remote automation and mission-critical communication systems.