Arc-flash hazard analysis

Arc flash analysis module

General

The module is compliant with industry-recognised standards and methods to perform arc-flash hazard calculations for industrial, distribution and transmission systems. These standards are:

• NFPA-70E 2015, Electrical Safety Requirements for Employee Workplaces
• CSA Z462, Workplace Electrical Safety Standard
• IEEE-1584 2011, Guide for Performing Arc-Flash Hazard Calculations

Algorithms

For the arc flash analysis in distribution and transmission systems, algorithms are available to cater for line-to-ground faults, which represent about 80% of the faults occurring on a distribution system. This added functionality facilitates the evaluation of arc-flash hazards on any part of any network.

The new algorithms are based on:

• NESC 2012
• OSHA; to be used with single-phase arc in the open air
• Lee method
• Wilkins method
• Heat transfer model, based on heat flux calculations (model published in the Electrical Safety Handbook by John Cadick, Mary Capelli-Schellpfeffer, Dennis K. Neitzel, published by McGraw-Hill Professional, 2001, Chapter 3.52)

The bus data of any network created with Eaton's CYME software can be supplemented with arc-flash related information, such as working distance, bus gap, connected equipment and exposed circuit enclosed in a box or in the open air. In addition, the module calculates the maximum bolted short-circuit levels at the desired work place (bus) for arc-flash hazard calculations.

Capabilities

• One-line diagram and user-friendly GUI for all systems
• Batch mode simulation that will allow the analysis of every bus in the network in one single simulation
• Short-circuit current can be calculated using ANSI or conventional fault calculation methods. Using ANSI, the reduced fault contribution of motors and generators is taken into consideration
• Machine and inverted-based DG contribution and duration of contribution
• Multiple contribution calculation
• Calculation using default values, depicted by standards or using user-defined values
• Accurate opening time is obtained from the protective device time-current curve library
• The module is equipped with the automatic detection and validation of protection schemes in the network
• Option to select the faster protective device, according to the time-current curves of the devices available at a given situation
• Results displayed in a tabular report
• Results box to visualise the results of selected points on the network

Warning labels

The program generates warning labels that are ready to be printed and affixed to electrical equipment. Different label templates are available and it is also possible to create customised warning labels.

These warning labels include all the necessary information, such as:

• Arc-flash hazard boundary
• Incident energy
• Hazard/risk category class.
• Personal protective equipment (PPE)
• Potential shock hazard
• Limited, restricted and prohibited approach boundaries
• Equipment node ID or downstream equipment identification