html{display:none} Substation Automation | Schweitzer Engineering Laboratories

Substation Automation

Simplify substation operations and increase the security and reliability of your electric power system.


SEL substation automation solutions enable you to analyze, visualize, and act upon the wealth of data captured by substation IEDs—helping you improve system control, protect valuable equipment, mitigate cyber threats, and comply with safety and security standards.

We offer products and services for every step in modernizing and automating your substations:

  • Visibility into system operationsImplement secure data and event collection, visualization, and analysis to increase situational awareness and gain insight into functional performance at both the grid and system levels.
  • Asset monitoring and predictive maintenanceKeep high-value assets online by detecting incipient failures and directing preventive maintenance programs.
  • Automated protection and controlImprove CAIDI and SAIDI metrics, protect mission-critical power system components, and automate substation device coordination.
  • Workflow automationStreamline compliance reporting with automated data concentration, and produce audit-ready, actionable reports.
  • Secure communications—Improve cybersecurity and performance with a software-defined networking (SDN) solution that is designed for operational technology (OT) networks.

SEL solutions are modular and scalable, so you can begin modernizing your substations with modular components that meet up-front needs and scale up to full substation automation as time and budgets allow.

Visibility Into System Operations

SEL substation gateway and remote terminal unit (RTU) solutions leverage the capabilities of our hardened automation controllers to provide the foundation for substation HMI, data concentration, and SCADA integration. SEL automation controllers provide flexible RTU functionality with superior reliability, extended I/O contacts, and powerful automation and control capabilities.

The SEL-3350, SEL-3555, and SEL-3560 Real-Time Automation Controllers (RTACs) feature an integrated HMI with a local display port and remote access, eliminating the need for an additional computer in the substation and avoiding the security vulnerabilities of Microsoft Windows-based operating systems.

For industrial applications, the SEL automation controller also becomes a powerful gateway between the substation and the factory, using EtherNet/IP to exchange data for real-time monitoring, process control, and power system integration.

3350 main

SEL-3350 Automation Controller

The SEL-3350 (configured as an RTAC) provides a secure system visualization, monitoring, and control platform for your substation or plant. With a small 1U form factor and powerful automation, reporting, security, and control capabilities, it’s ideal for substation RTU applications.

  • You can collect event reports from various manufacturers’ relays and IEDs.
  • RTU capabilities include protocol conversion, SCADA communications, synchrophasors, time synchronization, data management, and an IEC 61131 logic engine powerful enough to handle virtually any automation task.
  • An optional integrated substation HMI with integrated DisplayPort output and secure web proxy makes it easy to visualize substation data and view other substation device web interfaces, all from one location.

SEL-2240 Axion

A fully integrated, modular control and I/O solution for utility and industrial applications. It combines communications, integrated security, and an IEC 61131 logic engine with a suite of I/O modules that provide high-speed, deterministic control performance over an IEC 61158 standard network.


SEL-3505/3505-3 Real-Time Automation Controller (RTAC)

A compact, low-voltage automation controller, ideally suited for low-power and limited-space applications.

Asset Monitoring and Predictive Maintenance

Asset monitoring and predictive maintenance—also known as condition-based monitoring (CBM)—help protect critical substation assets, save money, and increase your system’s reliability by detecting signs of wear and stress in critical substation assets and directing preventive maintenance to the equipment that needs it the most.

SEL automation controllers provide the advanced data recording and analysis capabilities that make asset monitoring and predictive maintenance possible, and they can be integrated with virtually any system you may have in place.

SEL Engineering Services teams integrate our devices with asset monitoring and predictive maintenance programs and combine CBM systems from multiple vendors into a single comprehensive solution.

Automated Protection and Control

Take advantage of the advanced capabilities and versatility of SEL protective relays, communications solutions, and automation controllers to provide SCADA integration and advanced power management and control.

With SEL devices, software, and services, you can implement condition-based equipment monitoring; automated data collection; coordinated protection; load management; fault location, isolation, and service restoration (FLISR) schemes; and more.

SCADA Systems

SEL designs, develops, tests, and deploys complete SCADA systems to monitor and control your systems or processes. Our experienced Engineering Services teams provide solutions ranging from IED integration and simple standalone implementations to complex networked systems.

SCADA System Design and Implementation

Digital Secondary Systems (DSSs)

SEL DSS solutions digitize measurements from primary equipment in the field and use fiber-optic cables to transmit the data to protective relays—eliminating the cost, complexity, and safety hazards associated with running copper cabling into the control house.

SEL Engineering Services implements two types of DSSs:

  • A point-to-point solution using SEL Time-Domain Link (TiDL) technology, which eliminates the need for network engineering, Ethernet equipment, and external time sources—and significantly reduces exposure to cyber threats.
  • A networked Sampled Values (SV) solution, which offers the flexibility of IEC 61850-9-2 and merging units with built-in protection.
More About SEL TiDL Technology

Automated Protection and Control

The reliability and versatility of SEL protective devices allow you to implement automated protection and load restoration schemes and achieve high levels of system availability with simple redundant solutions.

In addition, our powerful automation controllers and precise-time products enable wide-area control solutions for electric generation, transmission, and distribution systems as well as high-speed microgrid control and industrial power system management and protection solutions.

SEL solutions provide automated protection and control at the substation level and system-wide:

  • Implement FLISR to reduce outages and improve CAIDI and SAIDI metrics with SEL-engineered distribution automation controllers based on our RTAC platform.
  • Integrate and manage distributed energy resources (DERs) with the SEL-engineered, RTAC-based Grid Connect solution.
  • Set up advanced data monitoring to help protect and maintain high-value assets.
  • Use SEL Data Management and Automation (DMA) software to automatically collect oscillography and SOE information from system devices.
  • Implement volt/VAR management to improve your system’s power factor.

SEL-3555 Real-Time Automation Controller (RTAC)

Our most powerful automation controller, the SEL-3555 RTAC provides complete and flexible system control. It can provide a secure gateway, remote access, data concentration, protocol translation, logic processing, and distributed control for one substation or many. An integrated web HMI with a local display port eliminates the need for an additional computer.


SEL-3355 Automation Controller

This versatile, hardened industrial and substation automation controller can be configured as a computer or as a Blueframe application platform. As a computer, it handles even the most demanding computing applications and provides complete automation control and operator station functionality. In the Blueframe configuration, it provides a secure, scalable framework for OT software applications and data exchange.

3360 Family

SEL-3360 Compact Automation Controller

This powerful, compact automation controller can be configured as a computer for use in substations or on the factory floor—or it can be configured as a Blueframe application platform to provide a secure framework for OT software applications and data exchange. It is ideal as a kiosk computer, engineering workstation, or automation controller.


SEL-2488 Satellite Synchronized Network Clock

Well-suited for demanding power utility applications, like synchrophasors, IEC 61850-9-2 Sampled Values, traveling-wave fault location, and substations with multiple time synchronization requirements, SEL satellite clocks process Global Navigation Satellite System (GNSS) time signals and distribute precise time via multiple output protocols, including IRIG-B and the Network Time Protocol (NTP).

Workflow and Compliance Automation

Streamline workflows and regulatory compliance processes with SEL solutions and engineering services.

The SEL Blueframe Application Platform

SEL Blueframe is a secure, scalable platform for running OT software applications, such as the SEL DMA suite, which streamlines workflows and supports regulatory compliance efforts by enabling centralized device management and automated data collection.

Blueframe allows a seamless exchange of data between applications on the platform, minimizes the frequency of patches and upgrades, and offers security features to prevent unauthorized access and potential attacks.

It can be embedded in the SEL-3350, SEL-3355, and SEL-3360 automation controllers or deployed in virtual environments.

Digital Fault Recording (DFR) Systems

The SEL-3555 RTAC can be combined with the SEL-2240 Axion modular I/O and control unit to create DFR systems that exceed NERC PRC-002 standards.

SEL Engineering Services implements complete DFR solutions, installing all the necessary devices and software and configuring the system to collect essential data and output audit-ready reports.

NERC PRC Compliance

We offer a complete range of NERC PRC compliance services and solutions:

  • Data collection and review
  • Compliance checks
  • Risk identification and prioritization
  • Mitigation options and deployment plans
  • Corrective actions, including settings verified by SEL engineers
  • Compliance road maps and audit documentation reports
  • Testing and maintenance plans and training

DMA—Data Management and Automation

SEL DMA applications enable you to automate and simplify data collection and device management and to streamline regulatory compliance processes. These applications run on our secure, scalable, and customizable Blueframe application platform, which can be embedded in SEL automation controllers or deployed in virtual environments.


acSELerator Team SEL-5045 Software

acSELerator Team automates the collection of power system data from multiple devices and stores it in a central location for easy access and analysis with tools such as SEL-5601-2 synchroWAVe Event software.

Secure Communications

SEL provides the cyber-secure communications solutions that make substation automation possible.

Our communications products are built to the same reliability standards as our relays and automation controllers. They support multiple communications protocols, including DNP3 and IEC 61850 communications, so they can fully integrate with your existing devices and systems.

SEL SDN solutions—designed specifically for OT networks—eliminate common LAN security vulnerabilities with a deny-by-default software architecture that accepts communications only on preconfigured paths between authorized devices. This helps protect against attacks that originate from compromised devices on the LAN and also adds protection against unauthorized traffic that slips past firewalls.


SEL-2740S Software-Defined Network Switch

The deny-by-default SDN architecture improves LAN cybersecurity and streamlines network management, change control, and data collection for security audits. High-speed failover maintains IEC 61850 protection systems.


SEL ICON Integrated Communications Optical Network

The ICON is a WAN multiplexer that combines time-division multiplexing (TDM) and Ethernet transport options with a comprehensive range of data interfaces. Low latency and high reliability make it ideal for substation network applications. It can also provide a network-based time source for IED synchronization, making substations less vulnerable to local GPS signal loss.


SEL-3622 Security Gateway

A router, VPN endpoint, and firewall device for serial- and Ethernet-based IEDs, offering cybersecurity plus physical awareness sensors for ultimate tamper resistance.


SEL Unified Threat Management (UTM) Firewall

SEL UTM is an advanced cybersecurity system that embeds in the SEL-3355 Automation Controller. With stateful firewall tracking, deep-packet inspection, adaptive routing, and hardware failover, it enhances the security and resiliency of network communications between substations and the control center.

Proven Reliability and Lifetime Support

Every solution we provide comes with the most reliable devices and best warranty in the electric power industry—plus free technical support for SEL products and systems.

It’s been this way at SEL for 35 years and counting.

Our products are designed to withstand the world’s most challenging environments, exceeding all industry standards for temperature, shock, and electric stress. An optional conformal coating gives electronic components an extra level of protection against contaminants in extreme environments.

All SEL electronic products are designed, tested, and manufactured in North America, in facilities that we own and operate.

We practice secure supply chain management, and our quality management system is certified to ISO 9001 requirements.

Engineering Services

Let us partner with you to modernize and automate your substations. SEL Engineering Services designs and implements fully integrated automation solutions for:

  • SCADA integration and HMI for visualization and control of substation systems.
  • Asset monitoring and predictive maintenance.
  • Data collection for standards compliance.
  • Improving CAIDI and SAIFI customer reliability metrics.

Our expert engineering teams will consult with you at every stage of the project, from planning and design through commissioning of the system. We’ll install and configure all the necessary SEL equipment, integrate it with your existing infrastructure and processes, and ensure that the whole system meets your economic and operational objectives.

More About Substation Automation Services

Solutions in Action

Customer Story

System-Wide Automation Solution Prolongs Life of Existing Relays

Customer Story

Caribbean Utility Thwarts Island-Wide Blackouts

Success Story

SCADA Sheds Light on Texas Utility’s Power System

Industrial Power Management

SEL industrial power management and motor control solutions protect high-value assets and keep critical processes running.

Distribution Automation

SEL Engineering Services will configure and commission a distribution automation controller (DAC) solution that is configured specifically for your system.

Questions? Contact Us!

We’re happy to answer all your questions and help develop the best solution for your needs.

Contact Engineering Services


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.