Westermo Merlin 3103 - 5G Industrial Cellular Router
5G NSA/SA, 2 x Gigabit Ethernet, Global 5G Bands, TPM Security, GNSS
The Merlin 3103 is a compact 5G cellular router engineered for industrial IoT and smart grid modernization. It consolidates multiple SCADA protocols (IEC 60870-5-104/101, IEC 61850, Modbus TCP, DNP3) through a single 5G or LTE connection, enabling real-time data transmission and remote management across distributed utility and industrial networks.
The Merlin 3103 delivers proven reliability with a 1.524 million hour MTBF and demonstrates the engineering maturity of the Merlin platform. Integrated cybersecurity architecture includes Trusted Platform Module (TPM) hardware for cryptographic key protection, Secure Boot to prevent unauthorized software modifications, and industry-standard IPSec encryption. Native GNSS support enables precise location tracking and time synchronization for distributed infrastructure monitoring.
Key Features
- 5G Ready Connectivity
- 5G NSA and SA mode support with global band coverage (28 5G NR bands)
- Fallback to LTE Cat-4 and 3G ensures continuity in maturing 5G networks
- 2 x Gigabit Ethernet ports enable high-speed local connectivity
- Multi-Protocol SCADA Gateway
- Bridges legacy SCADA devices (IEC 60870-5-104/101, Modbus TCP, DNP3) and modern systems (IEC 61850) through a single outbound connection
- Native protocol conversion and gateway functionality reduce field wiring and simplify integration
- Industrial-Grade Security
- Trusted Platform Module (TPM) secures cryptographic keys independent of system firmware
- Secure Boot prevents unauthorized software modification
- 802.1X authentication, IPSec encryption, and stateful firewall as standard
- Integrated Location Awareness
- GNSS (GPS, GLONASS, BeiDou, Galileo) support enables precise location tracking for distributed assets and infrastructure monitoring
Typical Applications
- Smart Grid & Utility Modernization
- Remote substation monitoring with 5G connectivity
- Distribution automation and distributed renewable integration
- Edge Computing & IoT
- Real-time data aggregation and localized processing
- Remote site connectivity in industrial IoT deployments
- Industrial Infrastructure
- Pipeline monitoring, water systems, distributed facility connectivity
Technical Specifications
| Specification |
Value |
| Standards Compliance |
EN/IEC 61000-6-2, EN/IEC 61000-6-4, EN 62368-1, RED Directive |
| Cellular Connectivity |
5G NR (n1/2/3/5/7/8/12/13/14/18/20/25/26/28/29/30/38/40/41/48/66/70/71/75/76/77/78/79), LTE Cat-4, 3G fallback |
| Network Interfaces |
2 × 10/100/1000 Mbit/s Gigabit Ethernet (RJ45) |
| Power Input |
9–36 VDC isolated, 10 W typical |
| Protocol Support (SCADA) |
IEC 60870-5-104, IEC 60870-5-101, IEC 61850, Modbus TCP, DNP3, MQTT |
| GNSS Support |
GPS, GLONASS, BeiDou, Galileo (passive antenna) |
| Operating Environment |
-20 to +70°C, 5–95% relative humidity, IP30 ingress protection |
| MTBF & Warranty |
1,524,000 hours (Telcordia), 5-year warranty |
Security Architecture
- Trusted Platform Module (TPM) stores and protects cryptographic keys independent of system firmware
- Secure Boot verifies and authorizes only manufacturer-signed software, preventing unauthorized modifications
- IPSec VPN with IKEv2, X.509 certificates, AES-256, and SHA-512 for encrypted site-to-site connectivity
- 802.1X authentication and stateful inspection firewall for network access control
- MQTT protocol translation enables secure communication with cloud-based monitoring and analytics systems
Certifications & Standards
- EN/IEC 61000-6-2 (Industrial EMC Immunity)
- EN/IEC 61000-6-4 (Industrial EMC Emissions)
- EN 62368-1 (Safety – Communication Technology)
- RED Directive (Radio Equipment Directive) – Global 5G radio compliance