|Feeder Terminal Units (FTUs) remotely monitor the voltage, current, active power, and reactive power status of high-voltage lines. Data from multiple FTUs is then acquired by Feeder Remote Terminal Units (FRTUs) that facilitate distribution automation. However, because FTUs are often located in unmanaged areas, they can be vulnerable to cyber threats, necessitating the use of secure cellular routers to protect data communication between FRTUs and FTUs.
Moxa says its OnCell G4302-LTE4 LTE cellular router offers high-speed performance and reliable communication between FTUs and FRTUs at substations, enabling immediate detection of issues or anomalies in the system. Importantly, it also provides protection against potential cyber threats to ensure system security. The OnCell G4302 offers advanced security features based on an IEC 62443-4-2 certified OS, thus supporting cybersecurity for IP-based cellular architecture. A firewall can also be set up to only allow logins from recognized IPs, adding powerful protection against DDOS attacks. The VPN lets data be encrypted and protected against intrusions.
The OnCell G4302 secure cellular router is suitable for an FTU thanks to its small size, dual SIM slots, GbE RJ45 Ethernet ports, an RS-232/422/485 serial port, and built-in cybersecurity features. It helps the FTU establish secure LTE cellular connections with FRTU in power substations, detect device status, and determine the interface for connection recovery.
In a scalable power network, FTUs are distributed across different areas. Moxa’s GuaranLink 4-tier connection check is embedded in the OnCell G4302 cellular router, offering redundancy to maximise connectivity. When data transmitted to and from FRTUs is interrupted, the OnCell G4302 provides WAN redundancy as a backup. Such redundancy makes it possible to switch between physical and cellular interfaces, effectively reducing downtime and stabilising data communication between FTUs and the control centre.
The OnCell G4302 cellular router uses MXsecurity management software to monitor distributed devices and send alerts in case of link failure. MXsecurity keeps managers aware of the statuses of various OT devices and the overall state of network communication. Managers stay current on network health by notifications being issued when an FTU within the network exhibits any abnormal status or behaviour. Furthermore, centralised control of the security policy, firmware, and configuration enhances the overall security of the entire power system.