HD67C03-2-G43-B2 – Industrial RS232 - MQTT Broker Converter with LAN and LTE (DIN 4M)

HD67C03-2-G43-B2 – RS232 - MQTT Broker converter for IoT, telemetry and industrial automation.

The HD67C03-2-G43-B2 is an advanced industrial communication converter designed to integrate legacy and modern RS232 devices with IoT platforms, cloud applications and data distribution systems based on the MQTT Broker protocol. This model belongs to the proven HD67C03 series, and the enhanced G43 variant adds a critical capability: an integrated LTE modem with SIM Card slot. The combination of Serial RS232, Ethernet 10/100 Base-T and LTE connectivity makes the HD67C03-2-G43-B2 one of the most versatile gateways for industrial telemetry, energy monitoring, environmental systems and remote IoT deployments.

The main role of the HD67C03-2-G43-B2 is to reliably convert data between RS232 devices and MQTT Broker environments. This allows sensors, controllers, analyzers, data loggers and industrial equipment using RS232 to communicate directly with IoT platforms, SCADA systems, cloud databases or local MQTT servers. Configuration is performed using the dedicated SW67C03 software, which provides full control over MQTT topics, RS232 transmission parameters, data mapping rules and network interface settings.

LAN + LTE connectivity – full flexibility for distributed and mobile systems

One of the key advantages of the HD67C03-2-G43-B2 is the dual communication infrastructure. The device is equipped with a standard Ethernet RJ45 port for wired MQTT communication, and additionally offers LTE connectivity via the integrated SIM Card modem in the G43 variant. This allows the gateway to operate in a wide variety of network conditions:

• full operation via LTE where no LAN is available,
• redundant communication paths (LAN + LTE),
• remote access independent of customer infrastructure,
• deployment in remote stations, cabinets, containers or field units,
• mobile and temporary installations with no wired connectivity.

This dual-channel communication approach ensures maximum reliability, making HD67C03-2-G43-B2 an excellent choice for mission-critical IoT systems that require continuous data delivery from RS232 devices.

Advanced RS232 support – up to 115200 bps

The Serial RS232 interface is available through a 3-pin 5 mm terminal block and supports transmission speeds up to 115200 bps. This allows integration with a wide range of industrial equipment including sensors, analyzers, PLC modules, laboratory instruments, industrial printers and monitoring systems. All transmission parameters such as baud rate, stop bits, parity, and flow control can be configured in the SW67C03 software to match the requirements of the connected device.

Stable MQTT Broker communication with 10/100 Base-T autosensing

The Ethernet interface supports 10/100 Base-T Autosensing, ensuring seamless integration into modern and legacy industrial networks. The HD67C03-2-G43-B2 can publish (PUBLISH) RS232 data to an MQTT Broker and subscribe (SUBSCRIBE) to topics to send commands back to RS232 devices. This enables scenarios such as remote control, telemetry, data acquisition and cloud integration using:

• Mosquitto,
• HiveMQ,
• EMQX,
• AWS IoT,
• Azure IoT Hub,
• Google Cloud IoT Core,
• local enterprise MQTT servers.

The MQTT configuration allows defining multiple topics, QoS levels, payload formats and publishing intervals, ensuring compatibility with any MQTT ecosystem.

Compact DIN 4M housing – easy installation in industrial environments

The gateway is built in a compact DIN 4M Modulbox housing (70 × 60 × 95 mm), making it easy to install in control cabinets, energy distribution boards, outdoor telemetry enclosures and industrial automation racks. This form factor ensures optimal use of space and simplifies integration into existing infrastructure.

Wide temperature and power range for demanding applications

The HD67C03-2-G43-B2 is designed for harsh industrial conditions. The device operates in a temperature range of −40°C to +85°C, making it suitable for outdoor and industrial settings. The power supply supports both 8–24 V AC and 12–35 V DC, ensuring compatibility with a wide variety of industrial power systems.

Typical applications

• RS232 - MQTT Broker integration in IoT environments,
• Telemetry and monitoring systems using LTE,
• Environmental and metering stations,
• Energy and utility networks,
• Remote SCADA integration via MQTT,
• Transport, mobile and temporary installations,
• Industrial IIoT applications with Serial communication.

Technical specifications

• RS232: 3-pin terminal block, up to 115200 bps
• Ethernet MQTT: RJ45, 10/100 Base-T Autosensing
• LTE SIM: yes (G43 variant)
• Power supply: 8–24 V AC / 12–35 V DC
• Operating temperature: −40°C / +85°C
• Dimensions: 70 × 60 × 95 mm
• Weight: approx. 200 g
• Software: SW67C03
• Mounting: DIN Rail (Modulbox 4M)
• Order code: HD67C03-2-G43-B2

Software SW67C03 for the model HD67C03-2-G43-B2 DOWNLOAD

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