ASME Y14.44-2008 pdf download.Reference Designations for Electrical and Electronics Parts and Equipment Engineering Drawing and Related Documentation Practices.
1.7 Definitions accessory: a basic part, subassembly, or assembly designed for use in conjunction with or to supplement another assembly, unit, or set contributing to the effec- tiveness thereof without extending or varying the basic function of the assembly or set. An accessory may be used fortesting, adjusting,orcalibratingpurposes. Typi- cal examples are test instrument, recording camera for radar set, headphones, and emergency power supply. assembly: a number of basic parts or subassemblies, or any combination thereof, joined together to perform a specificfunction. Typicalexamples areelectricgenerator, audiofrequency amplifier, and power supply. NOTES: (1) The application, size, and construction of an item may be fac- tors in determining whether an item is regarded as a unit, an assembly, a subassembly, or a basic part. A small electric motor might be considered as a part if it is not normally subject to disassembly. (2) The distinction between an assembly and a subassembly is not always exact; an assembly in one instance may be a subassem- bly in another where it forms a portion of an assembly. assembly, microelectronic device: an assembly of insepara- ble parts, circuits, or combination thereof. Typical exam- ples are microcircuit, integrated circuit package, and micromodule. attachment: a basic part, subassembly, or assembly designed for use in conjunction with another assembly, unit, or set, contributing to the effectiveness thereof by extending or varying the basic function of the assembly, unit, or set. A typical example is UHF converter for VHF receiver. basic part: one piece or two or more pieces joined together, which are not normally subject to disassembly without destruction of designed use. Typical examples are electron tube, resistor, relay, power transformer, and microelectronic device.
basic reference designation: the simplest form of a refer- ence designation consisting only of a class letter portion and a number (namely, without mention of the item within which the reference-designated item is located). complete reference designation: a reference designation that consists of a basic reference designation and, as prefixes, all the reference designations that apply to the subassemblies or assemblies within which the item is located, including those of the highest level needed to designate the item uniquely. partial referencedesignation: a reference designationthat consists of a basic reference designation and which may include, as prefixes, some but not all of the reference designations that apply to the subassemblies or assem- blies within which the item is located. NOTE: The reference designation for a unit consists of only a number. relay: anelectrically controlled (usually two-state) device that opens and closes electrical contacts to affect the operation ofother devices in the same or another electric circuit. set: a unit of units, necessary assemblies, subassemblies, and basic parts connected or associated together to per- form an operational function. [(“Set,” as used to denote a collection of like parts, such as a tool set or a spare set) is not a part of this Standard.] Typical examples are search radar set, radio transmitting set, and sound measuring set; these include such parts, assemblies, and unitsas cables, microphone, andmeasuringinstruments. subassembly: two or more basic parts which form a por- tion of an assembly or a unit, replaceable as a whole, buthavingapartor partswhichareindividuallyreplace- able. Typical examples are filter network and terminal board with mounted parts.
220.127.116.11 Sockets 18.104.22.168.1 Single-Item Mounting. A socket, fuse holder, or similar device that is always associated with a single particular part or subassembly (such as an elec- tron tube, a fuse, or a printed circuit board with or without integral contacts or connectors) shall be identi- fied by a composite reference designation consisting of the class letter X followed by the basic reference designa- tion that identifies the mounted part. For example, the socket for electron tube V6 would have a basic reference designation of XV6; the only socket for subassembly A4 would have a basic reference designation of XA4 (see Fig. 2). If the mounted item has two or more bases or connec- tors integral withthe item, suffixletters shall be assigned to each base of the item (according to para. 2.1.4). The sockets should then be identified as indicated above. For example, if electron tube V3 has two bases, A and B, the sockets would be identified as XV3A and XV3B.