Teltonika RUT956 Industrial 4G Router with RS232, RS485 and GNSS

Teltonika RUT956 industrial 4G router with serial, GNSS and I/O

The Teltonika RUT956 is a 4G LTE Cat 4 industrial router built for deployments where cellular connectivity, serial device integration, and location tracking are all required in a single unit. It carries dual Mini SIM slots plus an integrated eSIM, RS232 and RS485 serial ports, a dedicated GNSS receiver covering GPS, GLONASS, BeiDou, Galileo and QZSS, and four configurable I/O lines including an analogue 4-20 mA input and an SPST relay output. The aluminium enclosure operates from -40 to +75 °C and mounts on DIN rail, wall or flat surface.

Running RutOS – Teltonika’s OpenWrt-based firmware – the RUT956 supports Modbus TCP and RTU, DNP3, DLMS/COSEM, OPC UA, BACnet, and MQTT alongside a full VPN suite. Failover across dual SIM, wired WAN, and Wi-Fi WAN is configurable in RutOS and, once set up, switches automatically based on signal strength, data limits, or connection loss. The router is fully compatible with Teltonika RMS for remote management, FOTA, and alerting across large deployments.

Key features

• 4G LTE Cat 4: up to 150 Mbps down / 50 Mbps up with 3G and 2G fallback on European LTE FDD bands B1, B3, B7, B8, B20 and B28.
• Dual SIM + eSIM: two external Mini SIM (2FF) holders plus an integrated eSIM; auto-switch configurable on weak signal, data limit, roaming, or network denial.
• RS232 and RS485: DB9 RS232 with RTS/CTS flow control and 6-pin RS485 (full and half duplex, 300-115200 baud) for serial device integration and Modbus RTU gateways.
• GNSS: GPS, GLONASS, BeiDou, Galileo and QZSS with NMEA 0183 output, NTRIP client, geofencing, and TAVL/RMS server support.
• Rich I/O: 1 x digital dry input, 1 x galvanically isolated digital input, 1 x analogue input (0-24 V with 4-20 mA), 1 x open collector output, 1 x SPST relay (40 V, 4 A), plus digital I/O on the power connector.
• 4 x Ethernet: 1 x WAN and 3 x LAN, all 10/100 Mbps RJ45, with the WAN port reconfigurable as LAN in RutOS.
• Wi-Fi 4: 802.11b/g/n access point and station modes, WPA3-SAE and WPA2-Enterprise security, up to 100 simultaneous clients.
• Industrial protocols: Modbus TCP/RTU client and server, DNP3, DLMS/COSEM, OPC UA, BACnet/IP, MQTT broker and publisher, Data to Server via HTTP(S) and Azure MQTT.
• VPN suite: OpenVPN, WireGuard, IPsec (IKEv1/IKEv2), GRE, L2TP, PPTP, ZeroTier, Stunnel, DMVPN, SSTP, Tinc.
• Passive PoE input: 9-30 V DC via LAN1 spare pairs (Mode B). Not compatible with IEEE 802.3af, 802.3at or 802.3bt – only use a matched passive PoE injector.

What is the RUT956 used for?

Remote substation and SCADA telemetry

Energy utilities connect the RUT956 to IEDs and RTUs via RS485 using Modbus RTU or DNP3 over serial, with data forwarded over cellular to a SCADA head end via Modbus TCP or DNP3 TCP. The isolated digital input and relay output allow event-driven alerting and remote switching. A fixed IP SIM removes carrier-grade NAT from the data path, enabling reliable inbound VPN tunnels for SCADA polling.

Smart metering and DLMS/COSEM data collection

The RUT956 supports DLMS/COSEM over both RS232/RS485 and TCP, making it a direct fit for smart metering concentrators connecting to electricity, gas and water meters. The analogue 4-20 mA input accepts signals from pressure transducers or flow meters on the same unit, reducing field hardware. GNSS timestamps data collection events for audit purposes.

ANPR and traffic monitoring

The RUT956 suits roadside ANPR deployments where cameras connect via Ethernet LAN, cellular backhaul is the only connectivity option, and GPS coordinates are required for incident logging. The SPST relay output triggers barriers or signals, and the isolated input can receive detector loop signals. GNSS geofencing in RutOS generates RMS alerts when a mobile installation moves outside a defined zone.

EV charge point management

EV charge points using OCPP over TCP route traffic through the RUT956 on cellular WAN. The router’s dual SIM failover – once configured in RutOS – keeps OCPP sessions active if the primary SIM loses connectivity. RS485 connects to energy meters for local load management, and the analogue input monitors supply voltage. See our explainer on 4G and 5G connectivity for EV charge points for more detail.

Vehicle and asset tracking

Fleets and mobile assets use the RUT956 for combined connectivity and GPS tracking via TAVL or RMS. GNSS coordinates are sent to a tracking server over MQTT or Data to Server on a configurable interval. The I/O juggler in RutOS triggers SMS or RMS alerts on ignition, door open, or geofence breach. The -40 °C cold start rating suits vehicles operating in northern Europe through winter.

Building management and industrial automation

The RUT956 supports BACnet over RS485 and TCP, and OPC UA client/server over TCP, covering a broad range of BMS and automation controllers. Digital I/O connects directly to dry-contact sensors, alarm outputs, and control relays without an additional I/O module. SNMP v3 integrates the router into network management platforms alongside other site infrastructure.

Pro tip

The RS485 port on the RUT956 runs full duplex on 4 wires or half duplex on 2 wires, configurable in RutOS. If you are connecting to a half-duplex Modbus RTU network with multiple slaves, set the port to half duplex and enable the Modbus gateway function. The serial Modbus gateway maps RTU slaves to Modbus TCP registers, so a SCADA system on the LAN or over VPN can poll the field devices directly without a separate converter. Baud rate, data bits, parity and stop bits all match to your device’s configuration in the RutOS serial settings page.

Building a resilient cellular connection

The RUT956 supports dual SIM failover, configurable in RutOS to switch on signal threshold, data limit, SMS limit, roaming, or connection failure. For critical deployments, use SIMs from two separate UK mobile networks to avoid single-operator outages. Ping reboot monitors connectivity at the application layer and triggers a modem restart if the target host becomes unreachable – this catches cases where the cellular bearer is active but routing has failed. Pair with a UPS on the DC input and monitor the deployment remotely via Teltonika RMS for FOTA updates and live signal alerts.

Frequently asked questions

What SIM cards does the RUT956 take?

The RUT956 uses Mini SIM (2FF) format in both external SIM holders. If you are used to handling Nano or Micro SIM cards from recent consumer hardware, you will need the SIM adapter kit included in the box, or source a 2FF SIM directly. For deployments needing a static, reachable IP address, a fixed IP SIM is strongly recommended – standard SIM cards sit behind carrier-grade NAT, which prevents inbound VPN connections and SCADA polling.

Does the RUT956 support eSIM?

Yes. The RUT956230100 (UK PSU variant) includes an integrated eSIM. It supports bootstrap eSIM provisioning for remote profile download and removal, storing up to 7 profiles. The eSIM can be used alongside or instead of the physical SIM slots. Our IoT eSIM service is compatible – call us to confirm the right profile for your deployment.

What is the difference between the RS232 and RS485 ports on the RUT956?

Both ports are independent. RS232 uses a DB9 connector with RTS/CTS hardware flow control, suited to point-to-point connections with a single device such as a GNSS receiver, legacy modem, or barcode scanner. RS485 uses a 6-pin industrial socket and supports multi-drop bus wiring with up to 32 devices (full or half duplex), making it the right choice for Modbus RTU networks, DLMS/COSEM meter buses, and DNP3 serial networks. Both can run simultaneously in RutOS.

Is the passive PoE input compatible with my 802.3af PoE switch?

No. The RUT956’s passive PoE input operates at 9-30 V DC on the spare pairs (Mode B) and is not compatible with IEEE 802.3af, 802.3at or 802.3bt standards. Standard PoE switches and injectors operate at 48 V and will damage the router. You must use a matched passive PoE injector operating within 9-30 V DC. See our guide to PoE on cellular routers before connecting.

Does the RUT956 support Teltonika RMS?

Yes, the RUT956 is fully supported by Teltonika RMS. From RMS you can monitor signal strength, manage configuration profiles, trigger FOTA firmware updates, set up alerts, and access the RutOS web interface remotely without a VPN. RMS requires credits per device per month. We stock Teltonika RMS credits for purchase alongside the router.

What mounting options does the RUT956 support?

The RUT956 supports DIN rail, wall mount, and flat surface mounting. None of the mounting kits are included in the standard box – they are sold separately. The standard package includes the router, a 9 W UK PSU, two mobile SMA antennas, two Wi-Fi RP-SMA antennas, a GNSS adhesive SMA antenna, a connectors set, a 1.5 m Ethernet cable, and a SIM adapter kit.

Related products and further reading

If you need dual SIM but no serial ports, the Teltonika 4G router range includes options at lower price points. For serial connectivity without GNSS or analogue I/O, look at the RUT906. If your deployment requires 5G throughput alongside serial interfaces, the RUTM series is the step up. We also stock a range of 4G antennas compatible with the RUT956’s SMA connectors, and fixed IP SIM cards suitable for SCADA, ANPR, and EV charge point use cases.