Robustel R2120 POE 4G Router, Ethernet and Wifi 5

Robustel R2120

The Robustel R2120 is an industrial dual-SIM 4G router with four PoE-PSE Ethernet ports. It connects and powers remote IP devices from a single unit. It runs RobustOS, Robustel’s OpenWrt-based Linux, and pairs 4G LTE with five Gigabit Ethernet ports, dual-band Wi-Fi, an RS-485 serial port and digital I/O. The four PoE ports feed cameras, sensors and access controllers over the same cable that carries their data. A remote CCTV or ANPR site then needs one box, not a router plus a separate PoE switch. RCMS cloud management is built in.

Key features

• PoE-PSE on four ports: ETH1 to ETH4 supply power to connected devices to IEEE 802.3af and 802.3at, up to 30 W per port.
• Dual-SIM 4G LTE: two Mini SIM (2FF) slots give carrier redundancy with automatic failover once configured in RobustOS.
• Five Gigabit Ethernet ports: 1 x WAN plus 4 x LAN, or all five ports as LAN.
• Dual-band Wi-Fi: 802.11ac 2×2 MIMO on 2.4 GHz and 5 GHz, access point or client mode.
• RS-485 serial: Modbus RTU to TCP gateway for PLCs, meters and legacy serial equipment.
• Digital I/O: 2 x digital input and 2 x digital output, opto-isolated, for alarms, gates and simple control.
• RobustOS with SDK: OpenWrt-based Linux with a documented C and C++ SDK.
• VPN suite: IPsec, OpenVPN, WireGuard and GRE, plus DMVPN, L2TP and PPTP as apps.
• RCMS cloud management: remote monitoring, firmware updates and PoE device reboots from one dashboard.
• Rugged build: aluminium housing, -20 to +70 degrees C operating range, DIN rail, wall or desktop mount.

What is the Robustel R2120 used for?

Remote CCTV and NVR sites

Power up to four IP cameras or an NVR directly from the router’s PoE ports and backhaul the footage over 4G. Dual-SIM failover keeps the link up if one network drops. From RCMS you can reboot a frozen camera remotely, so a locked device does not force a site visit.

Car parks and ANPR

Drive boom barriers from the digital outputs, read loop detectors on the digital inputs and power ANPR cameras over PoE. The 4G link sends plate data to your parking platform. A fixed IP SIM lets that platform reach the router for two-way control.

Street lighting and smart city cabinets

Connect lighting controllers over Ethernet or RS-485 and manage dimming schedules across an encrypted VPN. The RS-485 port speaks Modbus RTU to legacy controllers and forwards it as Modbus TCP, so older kit joins the IP network without a separate gateway.

Industrial and utility monitoring

Bring Modbus RTU meters, PLCs and RTUs onto an IP network through the RS-485 port. Digital inputs flag door contacts, tamper switches or pump status. Digital outputs trigger local action, such as an alarm or a relay.

Temporary and construction site connectivity

One R2120 powers and connects site cameras, a local Wi-Fi network and wired devices. Dual-SIM covers patchy coverage, and DIN rail mounting suits a roadside or container cabinet.

Pro tip

The R2120 sources PoE, it does not receive it. To power devices on the PoE ports you must feed the router a 48 V DC supply, which is why the input range is 44 to 57 V DC rather than the 9 to 30 V DC common on smaller routers. The bundled adapter covers the router plus modest PoE loads. Four cameras at full 30 W, or long cable runs, need a larger 54 V DC supply. Size the PSU to your total PoE budget before you order.

Building a resilient cellular connection

The R2120 carries two SIMs, so you can split traffic across two mobile networks and fail over automatically once failover is configured in RobustOS. Pair it with a fixed IP SIM if you need inbound access for remote management or a VPN. For sites that must ride out a mains dip, run the router and its PoE loads from a 48 V UPS sized to your PoE budget. RCMS then monitors signal, data use and link state across the fleet, so you can act on a weak link before it drops.

Frequently asked questions

Does the Robustel R2120 have PoE in or PoE out?

PoE out. The four PoE ports are PSE, so the router powers connected devices such as cameras and access points. It cannot itself be powered over Ethernet. You power it from a 48 V DC supply on the locking 2-pin connector.

How many PoE devices can the R2120 power at once?

Four, one per PoE port, up to 30 W each. The total depends on your PSU. The bundled adapter runs the router plus lighter PoE loads. For four high-draw cameras, or long cable runs, fit a larger 54 V DC supply.

Does the R2120 support dual-SIM failover?

Yes. It has two Mini SIM (2FF) slots. Once you set failover in RobustOS, the router switches to the second SIM if the primary network drops. This model uses physical SIMs, not eSIM.

What is Robustel RCMS?

RCMS is Robustel’s cloud management platform. It gives you remote monitoring, over-the-air firmware and config updates, and remote PoE device reboots across your Robustel fleet from one dashboard. You can create a free RCMS account to get started.

What SIM card do I need, and can I manage the router remotely?

A standard Mini SIM (2FF) works for outbound data. For inbound access, such as reaching the router for remote management or a VPN, a fixed IP SIM is strongly recommended, because standard SIMs sit behind carrier-grade NAT. See our fixed IP SIM cards.

Which order code should I buy?

A015000004 is the full package: the router, two cellular antennas, two Wi-Fi antennas, a power adapter and a DIN rail kit. A015000001 is the router and DIN rail kit only, for installers supplying their own antennas and 48 V PSU. Both are the EMEA and SE Asia band variant (R2120-A5AAA-4L-A12EU).

Related products and further reading

Pair the R2120 with a fixed IP SIM for remote access, and browse our 4G antennas for cabinet and enclosure installs where the supplied stub antennas fall short. If you plan to run an inbound VPN, our guide to VPN on cellular routers covers the options. For pay-as-you-go connectivity, see our IoT SIM cards.