Autodesk 235B1-05A761-1301 User Guide - Page 822

angle of deflection The maximum allowable angle specified in the content indicating that male and female connectors are still considered connected. Angle of deflection (AoD) appears as Use fitting tolerance on the Piping Properties palette on page 286. annotation Text, dimensions, symbols, or reference marks added to drawings for clarification. annotation scale flag Elevation annotation used in place of linear measurements to show the height of pipes and fittings. annotation symbols Annotation used to clarify parts of a drawing, such as leaders, break marks, title marks, and revision clouds. See also annotation. APC For Autodesk Part Catalog. Standard file format for part catalogs within AutoCAD MEP. architectural elements Architectural objects such as doors, walls, and windows. See also AEC objects. ASHRAE fitting A duct fitting identified and described in the Duct Fitting Database of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). attribute An AutoCAD object that is included in a block definition to store alphanumeric data. Attribute values can be predefined or specified when the block is inserted. Attribute data can be extracted from a drawing and inserted into external files. ballast An electrical device used in fluorescent and HID fixtures. It furnishes the necessary starting and operating characteristics to the lamp for proper performance. base curve A curve used to define particular drawing objects, such as lines, polylines, and arcs. Many objects do not have a base curve and must be used with the curve anchor or layout curve command. See also curve anchor and layout curve. baseline An established but imaginary line on which objects can rest. bay In grid layouts, a regularly repeated spatial element defined by grid lines. bell/hub A joining method where the pipe or fitting has an enlarged end to accept the male end of a pipe or fitting. The depth of the connection is defined by the connection engagement length value. See also connection engagement length (CEL). bitmap The digital representation of an image having bits referenced to pixels. In color graphics, a different value represents each red, green, and blue component of a pixel. block A generic term for one or more AutoCAD objects combined to create a single object. branch circuits The circuits that carry power from the service panel to electrical devices. brazed (1) Made of brass. brazed (2) To unite metal with solder that contains copper, zinc, and other materials with high melting points. break marks (1) Annotation used to specify a shortened view of an elongated object or group of objects. break marks (2) To signify that an object has been broken or has had a piece removed. breaker An electrical device that connects or disconnects power to a circuit. BTU For British Thermal Unit. The amount of heat required to raise the temperature of one pound of water one degree Fahrenheit. building model A 2-dimensional (2D) or 3-dimensional (3D) representation of one or more building objects, such as architectural, structural, or building systems objects. butt weld A joint type where pipe is welded to other pipe, to fittings, or to equipment. No special joint fixture is required. The pipe end is prepared by grinding, and the pipe end is prepared by grinding, and then the pipe is directly welded. 804 | Glossary