D-Link DOM-311-TSO 4G LTE IIoT RTU

Highlights at a Glance

• Cellular WAN: 4G LTE Cat 4 with up to 150 Mbps downlink and 50 Mbps uplink over a single Nano SIM slot
• I/O integration: 3 digital inputs and 2 open-collector digital outputs for direct field-device control
• Serial connectivity: RS-232 and RS-485 terminal-block interfaces with Modbus TCP/RTU/ASCII support
• Secure remote access: OpenVPN tunnel and IPS firewall with MAC/IP filtering
• Flexible management: Web UI, SMS-based control, and D-ECS cloud platform for centralised device management
• Industrial mounting: DIN-rail form factor measuring 78 x 70 x 29 mm in a zinc-plated steel case

Cellular Connectivity & Networking

The unit provides cellular WAN over 4G LTE Cat 4, delivering a maximum downlink throughput of 150 Mbps and a maximum uplink throughput of 50 Mbps. A single Nano SIM slot serves the cellular interface, and two SMA (F) antenna connectors accommodate external antenna installations. The device operates across FDD bands B1, B3, B7, B8, B20, and B28A, plus TDD bands B38, B40, and B41.

On the LAN side, one Fast Ethernet port runs at 10/100 Mbps and provides DHCP server functionality. Network features include IPv4 and IPv6 support, port forwarding, NAT, and static routing. Dynamic DNS is supported through DynDNS, No-IP, and dynamic DO services.

Serial & Digital I/O

The RTU exposes one RS-232 and one RS-485 serial interface via terminal-block connections, enabling direct communication with legacy industrial equipment. Serial-to-IP virtual COM operation is supported in TCP client, TCP server, and UDP modes. The device implements Modbus TCP/RTU/ASCII for protocol-level integration with industrial control systems.

Three digital inputs accept logic-0 levels of 0–2 V and logic-1 levels of 5–30 V. Two digital outputs use open-collector circuitry rated for a maximum of 30 V, allowing the unit to drive external relays or indicators directly from the field.

Security & VPN

Remote site connectivity is protected by an OpenVPN tunnel for encrypted site-to-site or client-to-site communication. The integrated firewall provides intrusion prevention and port-forwarding rules, while MAC and IP filtering restrict access to authorised devices on the local network.

Management & Maintenance

Day-to-day configuration and monitoring are handled through a web-based UI accessible over the LAN. SMS-based management commands offer an out-of-band control path when IP connectivity is unavailable. For fleets of connected devices, the D-ECS cloud platform provides centralised management. System maintenance functions include firmware upgrade, reboot, and reset, all accessible through the web UI.

Power, Mounting & Environmental

The device accepts a DC power input ranging from 9 V to 36 V, accommodating the voltage rails common in industrial cabinets. It mounts on a standard DIN rail, and its enclosure measures 78 x 70 x 29 mm. The casing is constructed from zinc-plated steel. Storage temperature spans -40 to 85 °C, and operating humidity ranges from 10% to 95% non-condensing.

Compliance & Certifications

The product carries CE and UKCA markings, confirming conformity with applicable European and United Kingdom regulatory requirements. It also complies with EN 18031-1, EN 18031-2, and EN 303645 standards, addressing network security and consumer IoT baseline requirements relevant to industrial deployments.