The SKM Arc Flash Evaluation study module, by default, uses the published IEEE 1584 standard working distances based on the voltage level and the equipment type:
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To change the working distanced based on your engineering judgment, left-click on the desired bus name cell and then right click to display the menu. Here you can ‘unlink’ six different fields.
This will unlink the working distance for a bus(s) you have selected, not all buses.
To globally change the working distances for several buses, highlight the working distance cells in the Arc Flash Evaluation window. Right-click to display the menu and select Global Change.
You may now enter a new value for the working distance. This can only be done for cells that have already been unlinked.