HD67C03-2-G43-E-B2 – Industrial RS232 to MQTT Broker Converter with LAN, LTE SIM and eSIM

HD67C03-2-G43-E-B2 Converter – Industrial RS232 to MQTT Broker with LAN, LTE SIM and eSIM.

The HD67C03-2-G43-E-B2 is a high-performance industrial converter designed to connect RS232-based devices with modern MQTT Broker infrastructures. This makes the unit a key component for IoT, IIoT, telemetry, remote monitoring and any application requiring the transformation of legacy serial devices into fully network-integrated MQTT data sources. The G43-E variant adds complete network redundancy through LAN, LTE SIM and a fully integrated eSIM, ensuring uninterrupted communication even in remote or infrastructure-poor locations.

Operating in a robust Housing type B enclosure with DIN rail mounting and terminal block connectors, the HD67C03-2-G43-E-B2 is built for harsh industrial conditions. Its wide operating temperature range of -40°C to +85°C, compatibility with 8…24 V AC / 12…35 V DC power supplies and resilient mechanical design make it ideal for production lines, SCADA platforms, industrial automation systems, mobile applications and telemetry.

The unit functions as a MQTT Broker, able to publish, subscribe, process and route messages from both serial RS232 sources and MQTT clients. This allows full integration with cloud platforms, edge services, SCADA systems and industrial analytics.

RS232 to MQTT Broker – transforming serial data into modern IoT architecture

The HD67C03-2-G43-E-B2 provides seamless conversion between classic RS232 communication and MQTT Broker structures. This allows data from existing serial devices to be published or consumed through network-based IoT environments.

• RS232 communication up to 115200 bps,
• publishing RS232 data as MQTT messages,
• MQTT subscription for RS232 command delivery,
• payload conversion (JSON, Base64, numeric types),
• full compatibility with legacy industrial RS232 systems.

The internal MQTT Broker supports multiple clients, topic management, structured message handling and real-time data routing between serial and IP-based infrastructures.

LAN + LTE SIM + eSIM – full communication redundancy

The G43-E version offers three independent connectivity options:

• LAN (Ethernet RJ45) – primary network communication, configuration and MQTT routing,
• LTE SIM slot – mobile connectivity using standard SIM cards,
• Integrated eSIM – embedded mobile access for remote or carrier-managed deployments.

This triple-layer connectivity ensures:

• uninterrupted operation in case of Ethernet outages,
• deployment in remote, temporary or mobile installations,
• flexibility in choosing mobile operators via SIM or eSIM,
• support for remote industrial systems without wired infrastructure.

The mobile module, as specified in the technical manual, includes an SMA Female antenna connector and support for MicroSIM, ensuring compatibility with professional LTE installations.

Configuration via SW67C03 and integrated webserver

Configuration of the HD67C03-2-G43-E-B2 is performed using the SW67C03 Compositor software as well as the device’s integrated webserver. This combination provides fast deployment and full control over message mapping and serial parameters.

The configuration software allows:

• definition of RS232 parameters,
• MQTT topic management (publish/subscribe),
• client authentication and access control,
• message structure and payload mapping,
• firmware updates and network configuration.

The SW67C03 software can be downloaded here: DOWNLOAD

The device is also compatible with the ADFweb Discovery Tool, which simplifies device detection on the local network.

Industrial design – Housing type B and DIN rail mounting

The HD67C03-2-G43-E-B2 is designed for industrial reliability. Key design features include:

• Temperature range: -40°C to +85°C
• Dimensions: 70 × 60 × 95 mm
• Mounting: DIN Rail
• Power supply: 8…24 V AC or 12…35 V DC
• Power connector: 2-pin terminal block (5 mm)
• RS232 connector: 3-pin terminal block
• Weight: approx. 200 g

The device includes Ethernet–power isolation, rugged screw connectors and robust mechanical construction for extended industrial life, as documented in the technical manual.

Typical applications

• Integration of RS232 devices into IoT/IIoT systems,
• Telemetry, monitoring and remote diagnostics,
• Connecting loggers, controllers and sensors to MQTT,
• Edge computing environments,
• MQTT Broker for distributed automation systems,
• Mobile and remote installations using LTE / eSIM connectivity.

Technical specifications

• Ports: 1× RS232; 1× Ethernet; SIM card; eSIM
• RS232: up to 115200 bps
• Ethernet/LTE protocol: MQTT Broker
• RS232 connector: 3-pin terminal block (5 mm)
• MQTT connector: RJ45 + SIM
• MQTT data rate: 10/100 Base-T Autosensing
• Power supply: 8…24 V AC or 12…35 V DC
• Operating temperature: -40°C…+85°C
• Dimensions: 70 × 60 × 95 mm
• Weight: approx. 200 g
• Software: SW67C03
• Order code: HD67C03-2-G43-E-B2

If you need support with selecting the right RS232 to MQTT Broker converter or verifying system compatibility, our engineering team is ready to assist you.