2016 IEEE Pulp, Paper & Forest Industries Conference (PPFIC), 2016
Installations of electrical equipment and system designs that comply with well-known consensus st... more Installations of electrical equipment and system designs that comply with well-known consensus standards and national codes will meet or exceed minimum guidelines for safety and reliability. However, many within industry hold the belief that further attention should be paid to “safety by design” and “prevention through design” principles. In response, IEEE 1683, IEEE Guide for Motor Control Centers Rated up to and Including 600 V AC or 1000 V DC with Recommendations Intended to Help Reduce Electrical Hazards [1], has been written to address electrical safety for low voltage motor control centers and similar standards are in development for other types of equipment. IEEE 1683 is the first IEEE standard developed to specifically address equipment design, selection and installation practices with emphasis on methods to reduce exposure to shock and arc flash hazards. This paper is summary of the history and reasons that lead to the development of IEEE 1683 and an introduction to its application for safer low voltage motor control center applications.
Record of Conference Papers. Industry Applications Society Forty-Seventh Annual Conference. 2000 Petroleum and Chemical Industry Technical Conference (Cat. No.00CH37112)
Today's engineers are faced with an ever-increasing number of choices in the design of indus... more Today's engineers are faced with an ever-increasing number of choices in the design of industrial control systems. The selection of control voltage, while often perceived as a simple decision, has potentially the largest impact on the design and overall success of a system. This paper focuses on the comparison of application issues for two frequently used control schemes: 24 V DC and 120 V AC. Topics such as safety, device functionality, system design and wiring methods, reliability, and cost are explored to identify important considerations in the selection process
ElEctrical EquipmEnt installations and systEm designs that comply with well-known consensus stand... more ElEctrical EquipmEnt installations and systEm designs that comply with well-known consensus standards and national codes will meet or exceed minimum guidelines for safety and reliability. However, many within the industry believe that further attention should be paid to the principles of safety by design and prevention through design. in response, iEEE standard 1683 [1], has been written to address electrical safety for low-voltage motor control centers (mccs), and similar standards are in development for other types of equipment. iEEE 1683 is the first iEEE standard developed to specifically address
Petroleum and Chemical Industry Technical Conference, Sep 12, 1994
Fire protection in electrical control rooms can be a controversial subject, but it is an importan... more Fire protection in electrical control rooms can be a controversial subject, but it is an important one, especially in today's highly regulated society. The prospect of using sprinkler systems around electrical equipment can cause anxiety. Conducting a risk analysis, considering available options, selecting appropriate protection, and being prepared for emergency response will result in an optimum design and safe operation. One company's recommended practice serves as a basis for guidelines on how to choose appropriate fire protection for electrical control rooms.<<ETX>>
Conference Record of the 2000 IEEE Industry Applications Conference. Thirty-Fifth IAS Annual Meeting and World Conference on Industrial Applications of Electrical Energy (Cat. No.00CH37129), 2000
Electrical safety requires a combination of standards and enforcement processes that must be care... more Electrical safety requires a combination of standards and enforcement processes that must be carefully integrated so they work together. Two main standards are used to provide electrical safety in facilities: the International Electrical Technical Commission (IEC) system in Europe and the National Electrical Code (NEC). These two systems provide electrical safety when used separately, but using a mix of the
IEEE PES Power Systems Conference and Exposition, 2004.
This paper reports on the accomplishments of the IEEE 1584™ Working Group. This working group rai... more This paper reports on the accomplishments of the IEEE 1584™ Working Group. This working group raised money for testing, oversaw a significant amount of testing, analyzed the data, developed a new model for incident energy calculation and wrote IEEE 1584™ IEEE Guide for Performing Arc Flash Hazard Calculations. The paper discusses: the working group&amp;amp;amp;amp;amp;amp;amp;#x27;s starting point; the need for laboratory
Proceedings of 1996 IAS Petroleum and Chemical Industry Technical Conference
Article 505 of the 1996 National Electrical Code contains provisions for a hazardous area classif... more Article 505 of the 1996 National Electrical Code contains provisions for a hazardous area classification system commonly known as the Zone 0 concept. This change in the NEC will allow two separate and independent approaches for using electrical equipment in classified areas. Manufacturers will develop new and modify existing products to meet the standards for both systems. Users must decide if the benefits outweigh the costs of changing not only to the new products but also to new wiring methods.
ABSTRACT A common practice is to install a service disconnect or a main disconnect for a feeder s... more ABSTRACT A common practice is to install a service disconnect or a main disconnect for a feeder system in the same enclosure compartment as the downstream overcurrent protective devices. This can result in potential safety risks of shock and arc flash. This paper addresses the advantages and disadvantages of isolating a service disconnect for electrical service for industrial and commercial installations from the perspective of prevention through design. The paper compares shock and arc flash hazard for both cases when the service disconnect or a main breaker is isolated and when it is in the same enclosure.
This is an analysis of the number and types of arc-flash injuries reported by OSHA inspectors fro... more This is an analysis of the number and types of arc-flash injuries reported by OSHA inspectors from April 1984 through June 2007 in the U.S. It considers incidents and injury types by voltage class from 120 V to 240 kV, frequency of incidents by class of equipment and with common tools, and descriptions of several incidents. The incident descriptions show an appalling lack of training and judgment by those injured. This shows the need for more emphasis on deenergization before beginning work. OSHA, Occupational Health and Safety Administration, is part of the U.S. Dept. of Labor.
A series of previous papers has provided information regarding the arc flash hazard and methods o... more A series of previous papers has provided information regarding the arc flash hazard and methods of calculating its potential impact on persons working on or near the equipment. This paper extends that base of information by focusing on the arcing current level and duration in low-voltage circuits protected by circuit breakers (CBs). It describes a method of calculating incident energy
A series of previous papers has provided information regarding the arc flash hazard and methods o... more A series of previous papers has provided information regarding the arc flash hazard and methods of calculating its potential impact on persons working on or near the equipment. This paper extends that base of information by focusing on the arcing current level and duration in low-voltage circuits protected by circuit breakers (CBs). It describes a method of calculating incident energy and the flash protection boundary due to arcing occurrences in equipment protected by CBs. This method provides convenient procedures for determining these values for generic situations in which some details of the CB are not known. Further, it provides a process for determining these values in typical feeder and branch circuit applications involving common transformers and cable sizes and lengths. The values are needed to determine safe work practices and appropriate Personal Protective Equipment to comply with NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces.
I welcome the growing interest in arc-flash studies and thank Stokes and Sweeting for their inter... more I welcome the growing interest in arc-flash studies and thank Stokes and Sweeting for their interesting paper [1]. R. Lee certainly made many simplifying assumptions. The great value of his paper is that it succeeded in relating theoretical electrical power system arcing fault energy to the possible incident energy on employees in a quantitative way. Granted that it was crude, but it was the starting point for all arc-flash incident energy studies and programs. The Stokes and Sweeting paper is very critical of Lee's analysis and model. One test of the value of a model is looking at how well it compares to other models. Many people have found that Lee's method gives results that are remarkably close to the results obtained by applying IEEE 1584 to 480-V cases. In the 1584 guide, the Lee method is recommended only for cases over 15 kV or with bus spacing greater than 150 mm, and results are recognized to be very conservative for those cases. It should be noted that almost all industrial, commercial, and utility generation plant cases encountered in actual arc-flash studies involve possible arcs in enclosed equipment with tight bus spacing and a system voltage under 15 kV. IEEE 1584 offers an empirically derived model for those cases. Under arc modeling, [1] speaks of arcs self extinguishing in < 10 or < 40 ms. In the testing sponsored by the P1584 Working Group, we also experienced this problem. Depending on voltage, electrode spacing, box size, and perhaps other factors, the arc may or may not be sustained-the arc may last only until the trigger wire is burned away. However, test setups can be changed so that the arc will be sustained until switched off. Only test results obtained while using these setups were included in the P1584 Working Group test database. This enabled the development of a model that simulates the realworld case where protection may be set for a relatively long time. Reference [1] describes tests involving long horizontal electrodes pointed to the location where an employee might stand when operating the equipment. In these tests, the arc extended a considerable distance from the electrode tips toward the likely employee's location. While the authors of [1] told me that this type of equipment is used in Australia, I have never seen it. Later testing by others has been conducted to compare the results of testing with horizontal electrodes of long lengths and very short lengths, of the type that is common in standard North American and European equipment. These tests showed that the possible arc projection distance is much shorter for equipment with short horizontal buses. The IEEE Standards Association has approved the development of a second edition of the 1584 guide to extend the range of applications and to improve the preciseness of the calculations relative to realworld equipment. This next edition is expected to address different bus configurations and additional arc-flash hazards. A test program is being planned by a joint IEEE/NFPA Collaboration.
Twenty-five years after it was first proposed and after five years of heated debate, the 1996 Nat... more Twenty-five years after it was first proposed and after five years of heated debate, the 1996 National Electrical Code (NEC) includes a new way to classify hazardous areas contained in Article 505 "Class I Zones 0, 1, & 2 Locations". This article provides an alternative path to classify hazardous areas as Zones 0, 1 and 2 instead of the traditional Division 1 and 2.
n the July/August 2002 issue of this column, I noted that, for more than 20 years, IAS members ha... more n the July/August 2002 issue of this column, I noted that, for more than 20 years, IAS members have been at the forefront in advancing science and technology to better understand the arc-flash phenomena and applying this knowledge in the evolution of technologies, regulations, standards, products, and work practices to reduce the risk of injuries from the arc-flash hazard. Another significant chapter in this body of knowledge was completed in 2002 with the publication of the first edition of IEEE Standard 1584, Guide for Performing Arc Flash Calculations. This guide is now available for use in performing arc-flash hazard analysis studies and determining potential thermal incident energy exposure for people working on or near electrical equipment. IEEE Standard 1584 builds on previous advancements in estimating arc-flash incident energy. It is useful in meeting the requirements of National Fire Protection Assocation Standard NFPA70E-2000, Electrical Safety Requirements for Employee Work Places. NFPA70E provides very comprehensive requirements for developing and establishing an electrical safety program for the workplace. The arc-flash hazard calculations included in IEEE Standard 1584 enable quick and comprehensive solutions for arcs in singleor three-phase electrical systems, either of which may be in open air or in enclosures, regardless of the lowor medium-voltage available. Generally, only systems with a supply transformer rated 125 kVA and larger are considered as having possible arc-flash hazards. Designers or facility operators can use the guide to determine the arc-flash hazard distance and the incident energy to which employees could be exposed during their work on or near electrical equipment. IEEE Standard 1584 includes the following steps to determine incident energy and the arc-flash boundary: From a single-line diagram, identify buses and switching points of concern. List modes of operation so separate calculations can be done for each: one/ two utility supplies, operation on generators, secondary ties open/closed. Find the bolted fault current at each bus for each mode of operation and determine how much of it will flow through the protective device that will interrupt the fault. Deduct the fault current generated by motors and that which comes through an alternate supply. Calculate the arcing fault current in the protective device using the calculator included in the guide. Find the clearing time for the protective device from the timecurrent curves. Enter all data into the 1584 calculator, including grounding type, equipment class, protective device type, and the distance a person might stand from the possible arc. Review data for reasonableness and possible special circumstances that could impact results. The results from this analysis can be used in comparing system design options for reducing incident energy, selecting tools and safe work practices to minimize personnel exposure, deciding whether certain work can be safely performed on or near energized electrical equipment, and in the selection of personal protective equipment. Currently, IEEE 1584 only addresses thermal incident energy and does not provide methods for estimating other energy components of arc-flash events, including blast, acoustic, and electromagnet i c ene rgy . Addi t iona l information is available on the IEEE Standards Association Web site at http://grouper.ieee.org/groups/1584/ value.html. IAS
Fire protection in electrical control rooms can he a controversial subject, hut it is an importan... more Fire protection in electrical control rooms can he a controversial subject, hut it is an important one, especially in today's highly regulated society. The prospect of using sprinkler systems around electrical equipment can cause anxiety. Conducting a risk analysis, considering available options, selecting appropriate protection, and being prepared for emergency response will result in an optimum design and safe operation. One company's recommended practice serves as a basis for guidelines on how to choose appropriate fire protection for electrical control rooms.
2016 IEEE Pulp, Paper & Forest Industries Conference (PPFIC), 2016
Installations of electrical equipment and system designs that comply with well-known consensus st... more Installations of electrical equipment and system designs that comply with well-known consensus standards and national codes will meet or exceed minimum guidelines for safety and reliability. However, many within industry hold the belief that further attention should be paid to “safety by design” and “prevention through design” principles. In response, IEEE 1683, IEEE Guide for Motor Control Centers Rated up to and Including 600 V AC or 1000 V DC with Recommendations Intended to Help Reduce Electrical Hazards [1], has been written to address electrical safety for low voltage motor control centers and similar standards are in development for other types of equipment. IEEE 1683 is the first IEEE standard developed to specifically address equipment design, selection and installation practices with emphasis on methods to reduce exposure to shock and arc flash hazards. This paper is summary of the history and reasons that lead to the development of IEEE 1683 and an introduction to its application for safer low voltage motor control center applications.
Record of Conference Papers. Industry Applications Society Forty-Seventh Annual Conference. 2000 Petroleum and Chemical Industry Technical Conference (Cat. No.00CH37112)
Today's engineers are faced with an ever-increasing number of choices in the design of indus... more Today's engineers are faced with an ever-increasing number of choices in the design of industrial control systems. The selection of control voltage, while often perceived as a simple decision, has potentially the largest impact on the design and overall success of a system. This paper focuses on the comparison of application issues for two frequently used control schemes: 24 V DC and 120 V AC. Topics such as safety, device functionality, system design and wiring methods, reliability, and cost are explored to identify important considerations in the selection process
ElEctrical EquipmEnt installations and systEm designs that comply with well-known consensus stand... more ElEctrical EquipmEnt installations and systEm designs that comply with well-known consensus standards and national codes will meet or exceed minimum guidelines for safety and reliability. However, many within the industry believe that further attention should be paid to the principles of safety by design and prevention through design. in response, iEEE standard 1683 [1], has been written to address electrical safety for low-voltage motor control centers (mccs), and similar standards are in development for other types of equipment. iEEE 1683 is the first iEEE standard developed to specifically address
Petroleum and Chemical Industry Technical Conference, Sep 12, 1994
Fire protection in electrical control rooms can be a controversial subject, but it is an importan... more Fire protection in electrical control rooms can be a controversial subject, but it is an important one, especially in today's highly regulated society. The prospect of using sprinkler systems around electrical equipment can cause anxiety. Conducting a risk analysis, considering available options, selecting appropriate protection, and being prepared for emergency response will result in an optimum design and safe operation. One company's recommended practice serves as a basis for guidelines on how to choose appropriate fire protection for electrical control rooms.<<ETX>>
Conference Record of the 2000 IEEE Industry Applications Conference. Thirty-Fifth IAS Annual Meeting and World Conference on Industrial Applications of Electrical Energy (Cat. No.00CH37129), 2000
Electrical safety requires a combination of standards and enforcement processes that must be care... more Electrical safety requires a combination of standards and enforcement processes that must be carefully integrated so they work together. Two main standards are used to provide electrical safety in facilities: the International Electrical Technical Commission (IEC) system in Europe and the National Electrical Code (NEC). These two systems provide electrical safety when used separately, but using a mix of the
IEEE PES Power Systems Conference and Exposition, 2004.
This paper reports on the accomplishments of the IEEE 1584™ Working Group. This working group rai... more This paper reports on the accomplishments of the IEEE 1584™ Working Group. This working group raised money for testing, oversaw a significant amount of testing, analyzed the data, developed a new model for incident energy calculation and wrote IEEE 1584™ IEEE Guide for Performing Arc Flash Hazard Calculations. The paper discusses: the working group&amp;amp;amp;amp;amp;amp;amp;#x27;s starting point; the need for laboratory
Proceedings of 1996 IAS Petroleum and Chemical Industry Technical Conference
Article 505 of the 1996 National Electrical Code contains provisions for a hazardous area classif... more Article 505 of the 1996 National Electrical Code contains provisions for a hazardous area classification system commonly known as the Zone 0 concept. This change in the NEC will allow two separate and independent approaches for using electrical equipment in classified areas. Manufacturers will develop new and modify existing products to meet the standards for both systems. Users must decide if the benefits outweigh the costs of changing not only to the new products but also to new wiring methods.
ABSTRACT A common practice is to install a service disconnect or a main disconnect for a feeder s... more ABSTRACT A common practice is to install a service disconnect or a main disconnect for a feeder system in the same enclosure compartment as the downstream overcurrent protective devices. This can result in potential safety risks of shock and arc flash. This paper addresses the advantages and disadvantages of isolating a service disconnect for electrical service for industrial and commercial installations from the perspective of prevention through design. The paper compares shock and arc flash hazard for both cases when the service disconnect or a main breaker is isolated and when it is in the same enclosure.
This is an analysis of the number and types of arc-flash injuries reported by OSHA inspectors fro... more This is an analysis of the number and types of arc-flash injuries reported by OSHA inspectors from April 1984 through June 2007 in the U.S. It considers incidents and injury types by voltage class from 120 V to 240 kV, frequency of incidents by class of equipment and with common tools, and descriptions of several incidents. The incident descriptions show an appalling lack of training and judgment by those injured. This shows the need for more emphasis on deenergization before beginning work. OSHA, Occupational Health and Safety Administration, is part of the U.S. Dept. of Labor.
A series of previous papers has provided information regarding the arc flash hazard and methods o... more A series of previous papers has provided information regarding the arc flash hazard and methods of calculating its potential impact on persons working on or near the equipment. This paper extends that base of information by focusing on the arcing current level and duration in low-voltage circuits protected by circuit breakers (CBs). It describes a method of calculating incident energy
A series of previous papers has provided information regarding the arc flash hazard and methods o... more A series of previous papers has provided information regarding the arc flash hazard and methods of calculating its potential impact on persons working on or near the equipment. This paper extends that base of information by focusing on the arcing current level and duration in low-voltage circuits protected by circuit breakers (CBs). It describes a method of calculating incident energy and the flash protection boundary due to arcing occurrences in equipment protected by CBs. This method provides convenient procedures for determining these values for generic situations in which some details of the CB are not known. Further, it provides a process for determining these values in typical feeder and branch circuit applications involving common transformers and cable sizes and lengths. The values are needed to determine safe work practices and appropriate Personal Protective Equipment to comply with NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces.
I welcome the growing interest in arc-flash studies and thank Stokes and Sweeting for their inter... more I welcome the growing interest in arc-flash studies and thank Stokes and Sweeting for their interesting paper [1]. R. Lee certainly made many simplifying assumptions. The great value of his paper is that it succeeded in relating theoretical electrical power system arcing fault energy to the possible incident energy on employees in a quantitative way. Granted that it was crude, but it was the starting point for all arc-flash incident energy studies and programs. The Stokes and Sweeting paper is very critical of Lee's analysis and model. One test of the value of a model is looking at how well it compares to other models. Many people have found that Lee's method gives results that are remarkably close to the results obtained by applying IEEE 1584 to 480-V cases. In the 1584 guide, the Lee method is recommended only for cases over 15 kV or with bus spacing greater than 150 mm, and results are recognized to be very conservative for those cases. It should be noted that almost all industrial, commercial, and utility generation plant cases encountered in actual arc-flash studies involve possible arcs in enclosed equipment with tight bus spacing and a system voltage under 15 kV. IEEE 1584 offers an empirically derived model for those cases. Under arc modeling, [1] speaks of arcs self extinguishing in < 10 or < 40 ms. In the testing sponsored by the P1584 Working Group, we also experienced this problem. Depending on voltage, electrode spacing, box size, and perhaps other factors, the arc may or may not be sustained-the arc may last only until the trigger wire is burned away. However, test setups can be changed so that the arc will be sustained until switched off. Only test results obtained while using these setups were included in the P1584 Working Group test database. This enabled the development of a model that simulates the realworld case where protection may be set for a relatively long time. Reference [1] describes tests involving long horizontal electrodes pointed to the location where an employee might stand when operating the equipment. In these tests, the arc extended a considerable distance from the electrode tips toward the likely employee's location. While the authors of [1] told me that this type of equipment is used in Australia, I have never seen it. Later testing by others has been conducted to compare the results of testing with horizontal electrodes of long lengths and very short lengths, of the type that is common in standard North American and European equipment. These tests showed that the possible arc projection distance is much shorter for equipment with short horizontal buses. The IEEE Standards Association has approved the development of a second edition of the 1584 guide to extend the range of applications and to improve the preciseness of the calculations relative to realworld equipment. This next edition is expected to address different bus configurations and additional arc-flash hazards. A test program is being planned by a joint IEEE/NFPA Collaboration.
Twenty-five years after it was first proposed and after five years of heated debate, the 1996 Nat... more Twenty-five years after it was first proposed and after five years of heated debate, the 1996 National Electrical Code (NEC) includes a new way to classify hazardous areas contained in Article 505 "Class I Zones 0, 1, & 2 Locations". This article provides an alternative path to classify hazardous areas as Zones 0, 1 and 2 instead of the traditional Division 1 and 2.
n the July/August 2002 issue of this column, I noted that, for more than 20 years, IAS members ha... more n the July/August 2002 issue of this column, I noted that, for more than 20 years, IAS members have been at the forefront in advancing science and technology to better understand the arc-flash phenomena and applying this knowledge in the evolution of technologies, regulations, standards, products, and work practices to reduce the risk of injuries from the arc-flash hazard. Another significant chapter in this body of knowledge was completed in 2002 with the publication of the first edition of IEEE Standard 1584, Guide for Performing Arc Flash Calculations. This guide is now available for use in performing arc-flash hazard analysis studies and determining potential thermal incident energy exposure for people working on or near electrical equipment. IEEE Standard 1584 builds on previous advancements in estimating arc-flash incident energy. It is useful in meeting the requirements of National Fire Protection Assocation Standard NFPA70E-2000, Electrical Safety Requirements for Employee Work Places. NFPA70E provides very comprehensive requirements for developing and establishing an electrical safety program for the workplace. The arc-flash hazard calculations included in IEEE Standard 1584 enable quick and comprehensive solutions for arcs in singleor three-phase electrical systems, either of which may be in open air or in enclosures, regardless of the lowor medium-voltage available. Generally, only systems with a supply transformer rated 125 kVA and larger are considered as having possible arc-flash hazards. Designers or facility operators can use the guide to determine the arc-flash hazard distance and the incident energy to which employees could be exposed during their work on or near electrical equipment. IEEE Standard 1584 includes the following steps to determine incident energy and the arc-flash boundary: From a single-line diagram, identify buses and switching points of concern. List modes of operation so separate calculations can be done for each: one/ two utility supplies, operation on generators, secondary ties open/closed. Find the bolted fault current at each bus for each mode of operation and determine how much of it will flow through the protective device that will interrupt the fault. Deduct the fault current generated by motors and that which comes through an alternate supply. Calculate the arcing fault current in the protective device using the calculator included in the guide. Find the clearing time for the protective device from the timecurrent curves. Enter all data into the 1584 calculator, including grounding type, equipment class, protective device type, and the distance a person might stand from the possible arc. Review data for reasonableness and possible special circumstances that could impact results. The results from this analysis can be used in comparing system design options for reducing incident energy, selecting tools and safe work practices to minimize personnel exposure, deciding whether certain work can be safely performed on or near energized electrical equipment, and in the selection of personal protective equipment. Currently, IEEE 1584 only addresses thermal incident energy and does not provide methods for estimating other energy components of arc-flash events, including blast, acoustic, and electromagnet i c ene rgy . Addi t iona l information is available on the IEEE Standards Association Web site at http://grouper.ieee.org/groups/1584/ value.html. IAS
Fire protection in electrical control rooms can he a controversial subject, hut it is an importan... more Fire protection in electrical control rooms can he a controversial subject, hut it is an important one, especially in today's highly regulated society. The prospect of using sprinkler systems around electrical equipment can cause anxiety. Conducting a risk analysis, considering available options, selecting appropriate protection, and being prepared for emergency response will result in an optimum design and safe operation. One company's recommended practice serves as a basis for guidelines on how to choose appropriate fire protection for electrical control rooms.
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