Robust Solutions for Digital Secondary Systems

Modernize your substation by choosing from two SEL digital secondary system solutions that advance how you protect and control the primary equipment in your substation.

These solutions improve safety by moving high-energy signals out of the control house and reduce the costs associated with running copper wiring for protective relaying.

SEL SV Solution—Combining Protection in the Merging Units With the Flexibility of IEC 61850-9-2

SEL SV is a communications-centric digital secondary system solution that combines protection in the merging units with the flexibility of IEC 61850-9-2 to increase the reliability of your power system. The SEL-401 and SEL-421 Protection, Automation, and Control Merging Units digitize analog signals from primary equipment and transmit them to SV relays in the control house via an Ethernet network. SEL merging units have integrated, local protection that works in the event of a loss of communications between the merging unit and the relay. They can be paired with SEL-400 series SV relays or with other relays and devices that are IEC 61850-9-2–compliant, providing interoperability in user networks.

SEL SV technology allows you to create a robust and flexible Ethernet-based point-to-multipoint network using tools such as software-defined networks or VLANs to fit your application needs. You can use the SEL-2740S Software-Defined Network Switch to provide centralized traffic engineering and improve Ethernet performance. The switch acts as a transparent Precision Time Protocol (PTP) clock that supports the IEEE C37.238 power system profile, ensuring submicrosecond time synchronization of the end devices.

Questions? Contact Us!

If you have any questions about SEL products, services, solutions, or support, please contact us. Our service and support professionals are ready to provide the answers you need.

Unbeatable Support

SEL support teams are stationed in regional offices around the world and staffed with application engineers who are experts in our products and in power system applications.

Technical support for SEL-manufactured devices is always free. No matter how often you need to call or how long your SEL products have been in service, you’ll reach an SEL expert who can provide the service and support you need.

Our cybersecurity team is always ready with the information and resources needed to keep your OT networks and critical systems secure and working effectively. Cyber services support contracts can include incident response, audits, system hardening, and more, depending on your anticipated needs.

More about SEL warranty and support