How to select between a fixed circuit or a movable conductor in Arc Flash.

Users can specify only one parameter for individual buses. It can be designated as a "Fixed" circuit or a "Movable" conductor. This will affect the Shock Limited approach boundary printed on Arc Flash labels.

From the Arc Flash Options window, select the "Fault Current" tab. Click on the "Fixed or Movable for Each Bus.." button. The following screen will appear:

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A "Movable" bus will have a higher limited approach boundary compared to a "Fixed" bus. Limited Approach Boundaries are based on the voltage levels according to NFPA and are taken from the Shock Approach Boundaries Table.

The "Fixed or Movable conductor" list of buses can be sorted by the Bus Name, Bus Voltage, or by "Fixed/Movable":

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To globally change a group from Fixed to Movable boundaries, sort by Voltage. Select (highlighting) the buses with the same voltage and click "Global Change". Enter "Movable" and click "OK".

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Limited Approach boundary printed in the Arc Flash Label is reported only on the parameter selected, either Fixed or Movable, but not both. The Restricted and Prohibited Approaches also include any inadvertent movement.

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