This document explains the functionality of the SEL Underground AutoRANGER Fault Indicator (AR-URD). It defines the AR-URD AutoRANGER trip logic, principles of operation, fault indication options, inrush restraint, and testing and reset functions.
This paper discusses how the SEL-735 Power Quality and Revenue Meter exceeds the nonsinusoidal test requirements for ANSI 0.1 accuracy class compliance. It also illustrates why the SEL-735 is highly qualified for revenue metering applications in today’s challenging power system conditions.
This paper provides an overview of single event upsets (SEUs), including their causes, mitigation methods, and effects on SEL relays. It quantifies the impact that SEUs have on system protection and provides best practices for ensuring reliability.
This paper explores the implementation of PTP on various Ethernet architectures, including enhancements to provide PTP redundancy. In addition, the paper provides reasons to use PTP clocks and recommendations on the types of PTP clocks to select.
The purpose of this paper is to detail the cybersecurity risks on industrial control systems and discuss how to detect and counter these risks by applying processes and technology to keep these systems safely operating.
This paper describes the Chess Master project, sponsored by the U.S. Department of Energy, which will apply software-defined networking to advance energy sector network cybersecurity.
By using a defense-in-depth approach, you can provide read-only SCADA data and Syslog messages to corporate or other networks. The layered defense includes adding a perimeter network, read-only HMI and Syslog server, and a one-way data sending mechanism through SDN and unidirectional firewall rules.
This paper discusses the benefits of applying the new SEL-FT50/SEL-FR12 Fault Transmitter and Receiver System to enhance distribution system protection.
The principles of software-defined networking (SDN) offer significant benefits for operational technology (OT) networking by addressing the limitations of traditional Ethernet. Read more in this white paper.
This paper provides a brief overview of SEL’s Time-Domain Link Technology (TiDL) and IEC 61850 as digital substation solutions and assesses the cybersecurity posture of each.
This white paper describes the early days of programmable logic controllers (PLCs), the introduction of Modbus protocol, and some of the challenges involved today with device interoperability, specifically challenges related to register addressing and data type formatting.
This white paper discusses SEL Real-Time Automation Controller (RTAC) security concepts and provides configuration examples to empower engineers, technicians, and security personnel to protect critical cyberassets.
This white paper describes how to use the SEL Real-Time Automation Controller (RTAC) to build an automated system to continuously monitor and validate many of the components identified in the NERC PRC-005 standard.
This white paper addresses the design considerations for modifying transformer protection at an existing nuclear station and the SEL equipment that can be used to implement that design.
This white paper addresses the two main reliability concerns in NAND flash storage, what type of NAND flash memory is best suited for embedded computer systems, and how to optimize computer systems for maximum reliability of NAND flash storage.
This white paper provides both theoretical and real-world examples with questions and solutions that can be used to gain experience with symmetrical components.
This paper provides recommendations for testing SEL relays and guidance for developing a test program that is compliant with NERC PRC-005-2.
This document defines AutoRANGER® trip logic, inrush restraint (IR), installation considerations, fault indication modes, principles of operation, battery conservation, and test/reset methods.
Event reports continue to be an invaluable feature in microprocessor-based relays. Some events are relatively straightforward to analyze, and others require experience and considerable knowledge of the power system and protective relay system in order to find root cause. This session provides several advanced real-world event examples, time to evaluate them, and solutions.
Event reports continue to be an invaluable feature in microprocessor-based relays. Some events are relatively straightforward to analyze, and others require experience and considerable knowledge of the power system and protective relay system in order to find root cause. This session provides several advanced real-world event examples, time to evaluate them, and solutions.
This white paper provides both theoretical and real-world examples with questions that can be used to gain experience with symmetrical components. The full solutions to these questions can be found in the white paper "Tutorial on Symmetrical Components, Part 2: Solutions."
Event reports have been an invaluable feature in microprocessor-based relays since the initial introduction of the technology. The days of unknown root cause for an operation, lengthy outages, or unexplained test results are largely over due to this tool and the ability of engineers and technicians to use it. We must practice to become proficient at analyzing event reports. This session provides real-world event examples, time to evaluate them, and solutions.
Event reports have been an invaluable feature in microprocessor-based relays since the initial introduction of the technology. The days of unknown root cause for an operation, lengthy outages, or unexplained test results are largely over due to this tool and the ability of engineers and technicians to use it. We must practice to become proficient at analyzing event reports. This session provides real-world event examples, time to evaluate them, and solutions.
This white paper addresses another method of increasing the reliability of substation computers designing them to use error-correcting code (ECC) memory. The use of ECC memory minimizes the specific memory error class of single bit flips. Almost all server-class computers use ECC memory, but very few substation computers use ECC memory.
A minimal synchrophasor system consists of phasor measurement units (PMUs) and integrates the collected data into centralized operator displays. This approach, while providing an immediate benefit over existing supervisory control and data acquisition (SCADA) systems, misses many opportunities for additional power system improvements.
This white paper discusses how the versatile SEL-2505 Remote I/O Module can move contact information and control and monitor remote equipment safely, reliably, and economically.
This paper shows that the specific considerations of using ISM band spread-spectrum radio impact the protection scheme and give Mirrored Bits® communications a significant advantage over IEC 61850 GOOSE messages.
In this paper, the basic concepts of reliability are investigated, and the reliable use of two SEL devices as primary and backup protective relays is promoted.
This paper reviews ground fault protection and detection methods for distribution systems.
The SEL-421 has the unique ability to provide both line protection and Synchrophasor measurement. A frequent question is: how does this dual functionality affect relay performance?
Several people asked SEL what this supposed breach of the algorithm means to users of the SEL-3021 Serial Encrypting Transceiver. The short answer is that the reported SHA-1 compromise does not impact the SEL-3021.
The Facilities Department at Schweitzer Engineering Laboratories, Inc. (SEL) oversees and maintains the power system for seven buildings totaling over 250,000 square feet. This facility in Pullman, Washington, is the world headquarters of SEL. As a result of the company’s growing need for power, the Facilities and Property Manager initiated an investigation of the power system for the Manufacturing building.
Multifunction protective relays include comprehensive monitoring capabilities that can detect the alert and emergency states, minimize system disturbance and prevent system collapse.
As part of our overall mission to make electric power safer, more reliable, and more economical, SEL develops and provides innovative, simple to use, robust technologies to protect, automate, control, monitor, and analyze power systems. An essential element of this strategy is the development of appropriate communications technologies and protocols.
Communications processors, RTUs, and PLCs are used as integration and automation controllers around the world. In order to appreciate the differences, it is appropriate to consider all aspects of integration and automation needs within the power system.
Case study and description of Commonwealth Edison Jefferson 138 kV/69 kV substation instrumentation and control design using SEL protection, control, automation and communications products and technology to provide substation SCADA, monitoring, and automation.