White Papers
Read what GE's experts have to say regarding key industry issues and recent innovations. Learn which solutions can help you solve your toughest application challenges.
General Design/Safety/Arc Flash
2012 NFPA 70E - Ten Most Important ChangesThe 2012 Edition of NFPA 70E®, Standard for Electrical Safety in the Workplace, is the ninth edition of this electrical construction industry standard. This edition includes many changes and additions that affect worker safety. The most important of these changes are focused on arc flash and electrical shock hazards.
A Case for the Separated Double TieDiscusses the use of single tie breakers versus double tie breakers and the safety aspects associated with each scenario.
Getting Ready for Electric Vehicle Charging StationsDiscusses the standards to which they are designed and built, and describes the common features and options now available.
A Comparison of Aluminum vs. Copper as used in Electrical EquipmentThe intended purpose is to provide the user with the information necessary to make an informed decision on the selection of copper or aluminum conductors within electrical equipment.
Application Considerations for Series Combination Overcurrent Protective Devices (OCPD) in New InstallationsProper applications of series combinations of OCPD are critical to meet minimum reliability and safety considerations.
Arc Flash and Low Voltage/ Over-Current Protective Devices (OCPDs)An overview of the importance of conducting Arc Flash studies and how to interpret the results. You'll also learn about the different types of over-current protective devices and their role in mitigating the Arc Flash Hazard or reducing the Hazard Risk Category (HRC).
Design for SAFETYThis is part 1 of an ongoing series intended to give tips and suggestions to the electrical design engineer to design electrical distribution systems with safety for the end user as the primary concern. The concern with the worker's safety continues to increase and there are numerous items which can be specified and designs which can be implemented which will increase a worker's safety.
Design for SAFETY- Part 2Part 2 is aimed toward electrical distribution systems, which utilize services with overcurrent devices rated greater than 1200A. To enhance a workers safety, the designer must consider devices that remove the technician from hazardous conditions.
Direct Current (DC) - Critical Infrastructure Power SystemsDC power has been a proven technology since the days of Thomas Edison.
GE Arc Vault™ Protection SystemTo address the increasing concerns and standards around arcing faults, GE challenged our Global Research Center to develop a new, "active" method of detecting & removing an arcing fault.
Power Distribution Systems for the Beijing 2008 Olympic GamesThis paper addresses some power distribution solutions for the Beijing 2008 Olympics Games.
RELT - Reduced Energy Let ThruThe intent of this paper is to explain what RELT (Reduced Energy Let-thru) accomplishes, how it benefits electrical equipment users and how the system is implemented.
The Basics of Arc FlashThe goal of this article is to give the reader a basic understanding of what occurs during an arc flash incident, and an understanding of some of the terms used in qualifying the danger associated with such events.
The Three A's of Arc FlashIn 2007 GE conducted a survey of industry professionals working in facilities related to the oil and gas industry, pulp and paper industry, and power generation. The study results revealed what we called the problematic three A's of arc flash.
Zone Selective Interlocking On Instantaneous (I-ZSI) and Waveform Recognition (WFR)A newer technology like GEs zone selective interlocking with Instantaneous protection (I-ZSI) enabled all the time has been developed to provide safety and selectivity at the same time, all the time.
Ground Fault Protection
A Look at Value-Engineering Ground Fault ProtectionHere is a look at how to reduce the price of a typical ground fault project while keeping it sound and possibly even improving on it from a technical engineering perspective.
Avoiding GF Problems when Designing for Multiple Low Voltage SourcesThe purpose of this article is to point out some of the problems associated with meeting the requirements of providing equipment ground fault protection on multiple-source low voltage distribution equipment, both switchgear and switchboards, and how to contend with them.
Coordinating Ground Fault Protection with Phase Overcurrent ProtectionThis document examines the possibility of achieving selectivity between ground fault devices and standard downstream phase overcurrent protection.
Equipment Ground Fault Protection - Where It's NOT Required or PermittedHaving only a partial understanding of applying ground fault protection can result in added project cost, increased liability and defeating the very intent of the code.
Ground Fault Protection for Solidly Grounded Low Voltage SystemsThe intent of this publication is to provide a clearer understanding of the many considerations associated with ground fault protection to solidly grounded, low voltage systems.
Resistance Grounding Systems BasicsResistance Grounding Systems are used in industrial electrical power distribution facilities to limit phase-to-ground fault currents.
Integrated Low Voltage Switchgear System - Entellisys
Arc Flash Mitigation with Entellisys�Most customers and end users are concerned with safety, and the Entellisys switchgear safety features have some of the most comprehensive tools in the industry today.
Ground Fault Detection in Multiple Source Solidly Grounded Systems via the Single-Processor Concept for Circuit ProtectionModern power distribution systems, such as the common double-ended substation, contain multiple power sources integrated within one system. This presents significant complexity to the designer attempting to design a protection system that will not be fooled by circulating neutral currents. This paper describes how the "Single Processor Concept for Circuit Breaker Protection and Control" provides ways to address this sensing problem.
Innovation to Reality-Introducing State-of-the-Art Protection and Monitoring to Existing Low-Voltage SwitchgearIn this paper, the authors discuss a unique approach to low-voltage switchgear protection and the process of transitioning this concept to a realworld application. The paper describes the architecture and functionality of this approach and explains how a centrally controlled system can provide advanced monitoring and protection functions much more effectively than existing systems.
Protection, Control, Reliability and Diagnostic Improvements via Single-Processor Control of Circuit Breakers in Low Voltage SwitchgearIn this paper, the authors explore a protection-and-control architecture based on a single processor that provides all the protection and control functions for a lineup of low-voltage switchgear. How this method of protection changes the paradigm from individual circuit protection to system protection, while cost-effectively and significantly increasing system reliability and protection is discussed.
Metering
Electronic Power Meters - Guide for their Selection and SpecificationElectronic power meters vary widely in features and this range of features determines the price level of the meter. The purpose of this article is to help the reader select the right meter from the vast number of choices for their customers, matching the function and need of the meter with the value to the customer.
Insights into Starting-up Electronic MetersUse of electronic meters is widespread today for many good reasons, but few users realize these meters should undergo a startup process. Here are some insights from a field engineer's perspective as to what may be needed in order to have a successful installation.
OPC the "Enabling" SoftwareToday's demands on software interfacing capabilities far exceeds anything imagined when the market began supporting Windows' dynamic data exchange (DDE) programming interface for communication with devices. This paper will provide an insight into these developments and describe the new king on the block, OPC.
Submetering - A Practical ApproachMore than ever, submetering is being applied in industrial as well as the traditional commercial and residential applications to encourage conservation and increase productivity. This article will describe what it is, why it's important and how to effectively apply it.
Unlocking the Proprietary MessWho would possibly invest in equipment that restricts all their future purchases to that same initial manufacturer? Well, it happens every day and it could easily happen to you. The ability for equipment to communicate is so prevalent today most specifiers feel confident in specking it. But how does it communicate and what will understand it? Unless you are aware of the pitfalls, you could tumble in. And if you already have, this article will help you dig out.
Motor Control Centers
A Primer on Low Voltage Motor Control CentersThis article will focus on NEMA and will walk you through some of the various elements and tips when you are choosing or specifying an MCC.
Panelboards
Series Rating Circuit Breakers in PanelboardsInvestigates the potential for cost savings when using series rated circuit breakers instead of fully rated circuit breakers in panelboards.
Photovoltaic Systems
Practical Challenges - Utility Interconnections for a Retrofit PV systemDiscussion focuses primarily on commercial/industrial installations.
Power Monitoring and Control
Internet-Accessible Power Monitoring & Control SystemsAccessing electrical system information from any location allows the system manager to provide quicker command and control of intelligent devices. The Internet allows real-time access anywhere on the globe through open protocols.
Power Quality and Reliability
Applying Voltage Disturbance Remediation SystemsThis Application Note presents an overview of voltage disturbance remediation systems and a guide to their appropriate applications.
Assessing the Cost of Voltage DisturbancesWhile the quality of the incoming power supply voltage is fundamentally a technical problem, it is ultimately necessary to make a business decision prior to implementing a fix. This document goes over the three major cost elements of voltage disturbances.
The Importance of Reliable Control PowerWhile the advent of microprocessors has the potential to make power systems more reliable, easier to maintain, and simpler to diagnose, the underlying implementation of an appropriate power system design is often lagging, especially when it comes to supplying a reliable source of control power.
Paralleling Temporary Power at the Beijing 2008 Olympic GamesA brief insight and overview of some of the considerations made in order to provide the high level of reliability needed to add paralleling capability to the switchgear and meet the demands required by the power bureau and other key entities involved.
Service Capabilities for UPSUninterruptible Power Supplies, UPS equipment is used to maintain service to critical loads and improve uptime. Proper maintenance of the UPS should provide the owner with an Uninterrupted Revenue Stream, lower capital expenditures and lower long-term maintenance cost.
Variable Frequency Drives and Harmonic Abatement TechniquesGuidance on the use of harmonic mitigation solutions with GE AF-600 FP and AF-650 GP drives.
Protective Relaying
CT Saturation in Industrial Applications - Analysis and Application GuidelinesThis exploratory analysis shows that severely saturated CTs only slightly reduce short circuit tripping capabilities of GE Multilin's relays. Given the typically applied settings, there is no danger of a failure to trip from intantenous overcurrent functions even in extreme cases of very high short-circuit currents and low-ratio CTs.
Distribution System Feeder Overcurrent ProtectionThe intent of this publication is to give a better understanding of distribution overcurrent protection problems and some of the methods being used to solve them.
Generating Station ProtectionThis guide is concerned primarily with short circuit protection and protection for abnormal operating conditions for generating stations.
Inter and Intra Substation Communications: Requirements and SolutionsThis paper presents an outline of the communication requirements of the myriad of Intelligent Electrical Devices in existence in the substation today as well as the expectations of what second generation microprocessor based devices might be able to do.
Protection of Synchronous Generators during Unbalanced System ConditionsThis paper reviews the unbalanced current capabilities of generators, the system unbalance conditions that produce negative sequence currents and discusses the protection of generators for these conditions.
Shunt Capacitor Bank Fundamentals and ProtectionThis paper reviews principles of shunt capacitor bank design for substation installation and basic protection techniques.
Substation Transients and Solid State ControlThe general nature and origin of control circuit transients are now fairly well understood. Also much progress has been made in identifying the features of station layout and solid state equipment design to eliminate this problem.
The Art and Science of Protective RelayingA textbook on protective relaying by C. Russell Mason.
UCA 2.0: The GE ExperienceThis paper details the hardware and software considerations, issues encountered, and benefits enjoyed by GE and others in implementing the substation profile of UCA in a digital device.
Upgrading and Enhancing the Generator Protection System by Making Use of Digital SystemsConsidering a digital enhancement or upgrade offers the owner of installed generation equipment several unique advantages. These include more complete machine protection, diagnostics capabilities for greater productivity and maintenance optimization, life extension with minimal implementation, and the operational advantages of sequence of events, present values and communications capabilities.
Selectivity
Designing for Circuit Breaker Instantaneous SelectivityThis paper will focus on one specific aspect of the selective coordination challenge - coordination of the short circuit protection between low voltage circuit breakers.
Improving Selectivity & Arc-Flash Protection Through Optimized Instantaneous Protection SettingsIn today's power distribution systems, existing protection methods do not provide full selectivity and instantaneous fault clearing for expected fault current, including lower magnitude arcing currents simultaneously. This paper will discuss two methods that may change that.
Power System Selectivity: The Basis Of Protective CoordinationThe Intent of this article is to provide a brief primer about the essence of coordinating the basic protective components of the electrical power system, including circuit breakers, fuses and protective relays, and to enable the reader to review a plot of time current curves.
Short Circuit
Simple Methods for Calculating Short Circuit Current without a ComputerConcepts are shown step by step.
Short Circuit Current CalculationsThe purpose of this publication is to provide the system designer with information and procedures necessary to calculate short-circuit currents in industrial and commercial power systems.
Understanding Short Circuit Motor ContributionMotor's contribution is the current generated by a motor or motors during a short circuit condition.
Switchgear and switchboard
AKD-20 Low Voltage SwitchgearGEs AKD20 Low Voltage Switchgear has unique and innovative features, which by design, greatly reduces the arc flash incident energy (severity) and the likelihood (probability) of its occurrence.
Application of Switchgear and SwitchboardsThe choice of using either switchgear or switchboards must be based on many different criteria and the design of the power system requires thought be given to each one. Following are insights into just a few of the differences to help in making those decisions.
A Deeper Look into Switchgear and SwitchboardsThis document looks at whether to apply switchgear or switchboards and how to cost effectively use switchboard functionalities.
Paralleling SwitchgearParalleling is the operation in which multiple power sources, usually two or more generators, are synchronized and then connected to a common bus.
Power/Vac SwitchgearAn overview of the basic features and construction types for the Power/Vac line of medium voltage metal-clad switchgear equipment offered by GE.
Step Out of the Arc Flash Hazard ZoneHow remote is your switchgear?
Training and Education
Continuing Education ProgramGE Industrial Solutions provides numerous free training and continuing education opportunities focused on supporting the specification and design communities.
Navigating the WebA navigation guide for the Consulting and Design Engineer section of the GE Industrial Solutions website.
Transient Voltage Surge
Ballast Survival when Exposed to Commonly Found Transient Voltages (IEEE Paper)This white paper was developed to review the effects of exposing energy efficient commercial and industrial lighting ballast to transient surges.
Ballast Survival when Exposed to Commonly Found Transient Voltages (GE Document)This white paper was developed to review the effects of exposing energy efficient commercial and industrial lighting ballast to transient surges.
Substation Transients and Solid State ControlThe general nature and origin of control circuit transients are now fairly well understood. Also much progress has been made in identifying the features of station layout and solid state equipment design to eliminate this problem.
The Application and Selection of Lightning ArrestersThis article concentrates on circuits/systems 1000V and greater and provides the reader with some general guidelines for the appropriate selection and application of lightning/surge arresters.
The Influence of Cable Connections on TVSS PerformanceThis paper is provided to demonstrate the effects associated with cabling Transient Voltage Surge Suppressors (TVSS's). The ramifications of conductor type and length can be significant due to the added impedance they impose on the surge path.
Transformers
Dielectric Fluids for Transformer Cooling, History and TypesThis article is intended to provide the reader with some level of insight into the appropriate selection and application of dielectric fluids used in transformer cooling.
DOE Regulation ChangesWith more and more emphasis being placed on energy conservation for political, economic, and environmental reasons, it is incumbent on the design professional to be informed of the changes in codes, standards, and regulations/laws that will impact the recommendations and application of products they specify on projects.
Reverse Feeding Dry-Type TransformersThere are several issues that should be considered before reverse feeding a step-down transformer. This paper discusses reverse-feed application issues and the appropriate corrective actions.
Selecting Current Transformers - Part 1This paper offers a window into the complexity of selecting the correct current transformer for the application.
The Whyes of the Wyes - The Behavior of Transformer Y ConnectionsThe earliest transformers were of course single phase. With the advent of the three-phase system, two alternative methods of connection for transformers were offered - the delta and the Y. The Y connection must have appealed to the operators then, as it does now. It however didn't take the industry long to discover one problem after another arising out of the Y-Y connection with the primary neutral floating.
What You Should Know about Paralleling Power TransformersOne electrical design decision that must frequently be made concerns paralleling transformers. In most cases, we find economy is the key factor in this decision.
Zig-Zag TransformersThis article addresses the use of the Zig-Zag transformer
UL and NEC
NEC Changes that have Impact on DesignsChanges to the National Electrical Code (NEC) always result in adjustments to products or applications within the industry. The low voltage electrical distribution segment of the industry has never been immune to new code requirements, but four recent changes have had more impact than most of us can remember.
Underwriters Laboratory implemented UL 508A supplement SB to require compliance by UL authorized panel buildersThis white paper includes: Overview of code changes in NEC Article 409, Overview of UL508A supplement SB, How Short Circuit Current Rating is determined, and Process flow charts.
Critical Operations Power SystemsThis paper discusses Article 700, Emergency Systems, Article 517, Health Care Facilities, and finally Article 708, COPS, and provides some of the additional requirements of each Article.
UL 1449 3rd Edition - Effects on Lightning Protection SystemsDescribes some of the key changes to the UL 1449 3rd Edition standard and how they impact the installation requirements for lightning protection systems for electrical distribution systems under 1000 volts.