Arc (SCH)

This document is no longer available beyond version 17.1. Information can now be found here: Arc Properties for version 24

The Arc dialog.

The Arc dialog.


This dialog allows the designer to specify the properties of an Arc object. An arc is a non-electrical drawing primitive. It is essentially a curved line segment which can be used when, for example, creating graphical symbols, custom sheet borders and title blocks.

For information on how a placed arc object can be modified graphically, directly in the workspace, see Graphical Editing.


The Arc dialog can be accessed prior to entering placement mode, from the Schematic – Default Primitives page of the Preferences dialog. This allows the default properties for the arc object to be changed, which will be applied when placing subsequent arcs.

During placement, the dialog can be accessed by pressing the Tab key.

While attributes can be modified during placement, bear in mind that these will become the default settings for further placement unless the Permanent option on the Schematic – Default Primitives page of the Preferences dialog is enabled. When this option is enabled, changes made will affect only the object being placed and subsequent objects placed during the same placement session.

After placement, the dialog can be accessed in one of the following ways:

  • Double-clicking on the placed arc object.
  • Placing the cursor over the arc object, right-clicking and choosing Properties from the context menu.
  • Using the Edit » Change command and clicking once over the placed arc object.


  • Color - click the color sample to change the color of the arc, using the standard Choose Color dialog.
  • Radius - the radius of the arc, measured from its center point, to the center of the arc line.
  • Line Width - the width of the arc line. Available widths are: Smallest, Small, Medium, and Large.
  • Start Angle - the start angle of the arc, in degrees from the horizontal.
  • End Angle - the end angle of the arc, in degrees from the horizontal.
The arc is drawn in an anti-clockwise direction from the Start Angle to the End Angle. Enter a value between -360 and 360 for each of these angles.
  • Location X/Y - the current X (horizontal) and Y (vertical) coordinates for the center point of the arc. Edit these values to change the position of the arc in the horizontal and/or vertical planes respectively.
  • Locked - enable this option to protect the arc from being edited graphically.
If attempting to graphically modify an object that has its Locked property enabled, a dialog will appear asking for confirmation to proceed with the edit. If the Protect Locked Objects option is enabled on the Schematic – Graphical Editing page of the Preferences dialog, and the Locked option for that design object is enabled as well, then that object cannot be selected or graphically edited. Double click on the locked object directly and disable the Locked property, or disable the Protect Locked Objects option, to graphically edit the object.


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