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How do I change the working distance in my Arc Flash spreadsheet?

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:

Working Distance Equipment Type kV
24 inches (610mm) Switchgear ≤ 1
18 inches (455mm) Panel ≤ 1
36 inches (910mm) Switchgear > 1 & < 35
72 inches (1829mm) Switchgear > 35
18 inches (455mm) all others N/A

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.