Working with the Equipment Duty Scenario Comparison Report

The Equipment Duty Scenario Comparison Report contains the equipment and scenarios based on your selections in the one-line and in the Scenario Comparison Report Options (see Scenario Comparison Report Options). The information on the report is grouped by bus name and then by equipment name.

You can print the report, export it to Excel, or export it to a CSV file from this spreadsheet view.

Report Purpose

Normal configurations may have tie breakers open and buses fed from single feeds. During transition to a different switching configuration, such as during maintenance or an emergency/alternate supply, there may be brief moment that a bus may be fed from multiple sources. If a fault occurs in that state, the fault currents can be higher than in normal configurations. Power flow and arc flash will not require this transient configuration to be modeled as a scenario. However, it is important to evaluate this condition for short circuit duty as the equipment is required to withstand or interrupt the fault currents. The Equipment Duty Scenario Comparison report allows you to compare different configurations and identify the worst-case duty.

Best and Worst Case Calculations

For each scenario, the program determines either:

  • (ANSI) The higher of the 1/2 cycle duty percentage or interrupting duty percentage
  • (IEC) The higher of the initial duty percentage or breaking duty percentage

The best case scenario is the one with the lowest calculated percentage.

The worst case scenario is the one with the highest calculated percentage.

Note: "Interrupting duty" refers to 5 cycle ANSI short circuit currents. ANSI has ½ cycle, 5 cycle, and 30 cycle short circuit currents. “Breaking duty” is used for IEC. EasyPower uses the following breaking currents for IEC: 0.02, 0.05, 0.10, and 0.25 seconds.

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