Datum Identifier Commands (DraftSight Mechanical Only) (2024 SP1) You can use datum identifier commands to add a datum identifier and attach it to areas in a drawing. A datum is a plane, a straight line, or a point used as a reference to measure and locate geometric entities and geometric tolerances. You can use the following commands: AM_DatumIdentifier to create datum identifier symbols. AM_DatumIdentifierEdit to edit datum identifier symbols. Datum identifier symbols identify datum features for feature control frame symbols. For example, you can use a datum identifier symbol to mark the center of a hole. Elements of datum identifier symbols include: 1 Square frame 2 Datum identifier of two capital letters maximum 3 Leader arrow 4 Triangle symbol When you create a datum identifier symbol in a drawing, the software generates a label that contains the datum identifier enclosed in a rectangle. The datum identifier appears in all feature control frames that use the datum as a reference. A leader line connects the label to the datum on the drawing. The leader line may include a filled or empty triangle. The position of the triangle indicates the corresponding datum. You can attach datum identifier symbols on: A surface or on one extension line of a surface Visible lines such as extension lines, dimensions, or axes A hole, leader pointing to a hole, or feature control frame Parent topicDraftSight