Definition
When a fault occurs, the relay protection device outputs information about the operating elements, time, fault phase, and distance measurement, and generates waveform files. Remote transmission of action reports sends this information to the dispatch master station, centralized control center, or operation and maintenance mobile terminals, supporting rapid isolation and power restoration decisions. Power production control regions typically use dedicated networks, while cellular networks are more suitable as auxiliary channels for information regions, mobile maintenance, or emergency command vehicles.
Strict adherence to zonal protection is required: operations in control areas must not downgrade security levels due to cellular channels; if cross-zone transmission occurs, it must go through forward and reverse isolation devices and approval processes.
Technical Features
Report data should be protected by signatures and timestamps to prevent forgery. Large waveform recording files can be transmitted in segments and resumed from breakpoints, with summaries being prioritized for upload. On the network side, fixed addresses + whitelist combined with VPN are recommended.
SimtoLink supports card-level auditing and regional policies to prevent SIM misuse after device removal, and provides online rate monitoring to support SLA.
Use Cases
Distributed power access leads to changes in fault characteristics, requiring faster aggregation and analysis of protection information. During emergency repairs, mobile gateways transmit LCD screenshots of on-site protection and preliminary reports back via cellular.
The system should clearly specify which information can be transmitted via cellular networks and which must use dedicated networks, and include this in the annual security inspection.
Deployment and Operation Recommendations
During the project implementation phase, enterprises should bind the IoT SIM card numbers to device serial numbers, installation locations, power supply methods, and maintenance responsible persons one-to-one, and sync this information into the asset and operation system to form a traceable link from card issuance, modification, activation, suspension to eventual cancellation. For equipment involving cross-province allocation or cross-border delivery, roaming charges, real-name registration policies, and local data compliance requirements should be evaluated in advance. It is recommended to choose solutions with predictable costs that support remote network switching or eUICC, reducing the frequency of on-site disassembly, and reserving spare cards and emergency replacement processes to shorten fault recovery time. For terminals received in bulk, it is recommended to perform sampling network verification covering connectivity and charges before activating the entire batch, to reduce rework costs.
In terms of cybersecurity, it is recommended to configure dedicated APN or VPDN tunnels for production or critical infrastructure terminals, converge north-south traffic to enterprise-controllable boundaries, and link with identity authentication, bastion host remote maintenance, and operation auditing; for remote control and parameter writing capabilities, hierarchical authorization, time windows, and dual-person review should be set. Regular drills for weak network and primary/backup link switching should be organized, recording latency, packet loss, and recovery time as technical references for MLPS (Multi-Level Protection Scheme) assessment, industry regulatory inspections, or internal risk control reviews. For third-party outsourced operations, minimum permissions, session recording, and key custody responsibilities should be clarified to avoid account sharing.
In daily operations, card management platforms should be used to continuously track online rates, abnormal traffic, dormant terminals, and data plan utilization, integrating alarms with the ITSM work order system to achieve automatic ticket assignment and closure. SimtoLink can split data pools for enterprises by factory, line, or business domain, providing bulk device suspension/resumption, API integration, and billing allocation capabilities, supporting visibility, control, and sustainable cost reduction at large-scale points, while aligning card management insights with project budgets and cost centers to improve transparency.