Arc-Flash Hazard Calculations Research Articles

A Methodological Proposal to Calculate the Arc Flash Considering AC-DC Sources

The arc flash is one of the main hazards that electrical energy presents. Due to its importance, arc flash research has focused on Alternating Current (AC) electrical systems. However, a considerable increase in Direct Current (DC) systems has been observed, particularly in integrating new technologies such as generation with non-conventional energy sources, electric vehicles, and energy storage systems. Direct Current (DC) installations are exposed to the same dangerous situations as Alternating Current (AC) installations, so that no electrical installation can guarantee an arc flash-free situation. In this paper, calculations required to estimate the incident energy in AC and DC systems are methodologically described under guidelines established by the most current standards: IEEE Guide for Performing Arc-Flash Hazard Calculations of 2018 and NFPA E70 Standard for Electrical Safety in the Workplace of 2021. This work uses a case study of a hospital facility on the Island of San Andrés, Colombia.

A Practical Application of IEEE Standard 1584-2018: Additional Considerations

IEEE standard 1584-2018, “Guide for performing Arc-Flash Hazard Calculations,” presents new challenges in data gathering and equipment modeling due to the removal of the 125-kVA exception and addition of the ability to model electrode configurations (ECs) and enclosure dimensions. Engineers must now understand equipment construction and choose whether to field-measure equipment and use actual data or use the typical values presented in IEEE Standard 1584-2018.

Arc-Flash Hazard Calculations in a Electrical Distribution System with Distributed Generation for Electrical Safety Audit

Arc-Flash Hazard Calculations in a Electrical Distribution System with Distributed Generation for Electrical Safety Audit

Introduction to IEEE Standard 1584: Guide for Performing Arc-Flash Hazard Calculations, 2018 Edition

Since it was first published in 2002, IEEE standard 1584 has been the premier standard for arc-flash hazard arcing current, incident energy, and arc-flash boundary (AFB) calculations for an arc-flash incident. After extensive testing and model development and a validation period, the long-awaited revision of IEEE 1584 has been published. The purpose of this article is to introduce IEEE Standard 1584-2018, IEEE Guide for Performing Arc-Flash Hazard Calculations , to the industry. The model range and the rationale used for parameter selection is discussed for quantities such as voltage, bolted root-mean-square (rms) short circuit current, the gap between conductors, enclosure dimensions, fault duration, working distance, and system frequency. The rationale is provided for the selection of electrode configurations and various enclosure (box) sizes and arrangements. This model is based on more than six times the tests performed for the model used in the 2002 standard. It provides additional modeling of electrode configurations which were not included in the 2002 version. Some guidance on identifying electrode configurations is provided.

Current-Limiting Fuses: New NFPA 70-2017 Section 240.67, Arc Modeling, and an Assessment Based on the IEEE 1584-2002

When operating in current-limiting mode, current-limiting fuses can effectively mitigate the heat and pressure hazards associated with an arc event because they limit the current in the first one-quarter cycle and interrupt current flow in less than 8.3 ms. The effectiveness of current-limiting fuses is reinforced by their inclusion in NFPA 70E-2015: Note to Table 130.7(C)(15)(A)(b), Annex D.4.6, and Annex O.2.4(4). The incident energy levels associated with current-limiting fuses can be determined from the IEEE Standard 1584-2002, IEEE Guide for Performing Arc-Flash Hazard Calculations. IEEE 1584-2002 presents a method for directly determining incident energy without first determining arc current or arc duration. The fuse equations were derived from 600-V arc tests involving a range of current-limiting fuse sizes. These data are reviewed to assess the performance of current-limiting fuses in reducing arc energy in accordance with NFPA 70-2017 Section 240.67. The IEEE 1584-2002 equations are used to assess the performance of these fuses in comparison with an arc energy reduction maintenance switch and the combination of both technologies. The viability of predicting arc current and incident energy for installations involving current-limiting fuses and implementing NEC Section 240.67 using general arc models is discussed.

How to hamper hazards

This article reports on the accomplishments of the IEEE 1584 working group (WG). The working group has raised money for testing, oversaw a significant amount of testing, analysed the data, developed a new model for incident energy calculation, and wrote IEEE 1584, IEEE guide for performing arc flash hazard calculations. The article also discusses the WG's starting point, the need for laboratory testing, the test and analysis methods employed, the discovery from the testing, the development of the model and the guide, and the need for further work.