1、 AMERICAN NATIONAL STANDARD ANSI/ISA-5.1-2009 Instrumentation Symbols and Identification Approved 18 September 2009 ANSI/ISA-5.1-2009, Instrumentation Symbols and Identification ISBN: 978-1-936007-29-5 Copyright 2009 by ISA. All rights reserved. Not for resale. Printed in the United States of Americ
2、a. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise), without the prior written permission of the Publisher. ISA 67 Alexander Drive P. O. Box 12277 Research Triangle
3、Park, North Carolina, 27709 USA - 3 - ANSI/ISA-5.1-2009 Preface (informative) This preface is included for information purposes and is not part of ANSI/ISA-5.1-2009. This standard has been prepared as part of the service of ISA, The International Society of Automation, toward the goal of uniformity
4、in the field of industrial automation. To be of continuing value, this standard should not be static but should be subject to periodic review. ISA welcomes all comments and suggestions and asks that they be addressed to the Secretary, Standards and Practices Board; ISA; 67 Alexander Drive; P. O. Box
5、 12277; Research Triangle Park, NC 27709; Telephone: (919) 549-8411; Fax: (919) 549-8288, e-mail: standardsisa.org. The ISA Standards and Practices Department is aware of the growing need for attention to the metric system of units in general, and the International System of Units (SI) in particular
6、, in the preparation of instrumentation standards. The Department will endeavor to introduce SI-acceptable metric units in all new and revised standards, recommended practices, and technical reports to the greatest extent possible. Standard for Use of the International System of Units (SI): The Mode
7、rn Metric System, published by the American Society for Testing they include, but are not limited to, calculating devices, purge meters, sample handling systems, and instrument air sets. 2.5.5 Accessory instrumentation consists of devices and hardware that do not measure or control but are needed fo
8、r effective operation of the measuring, monitoring, or control system; they include, but are not limited to, flowmeter tube run, straightening vanes, and seal pots. 2.6 Extent of loop and functional identification 2.6.1 This standard provides identification codes and methods for the alphanumeric ide
9、ntification of monitoring and controlling loops, instruments and functions. 2.6.2 These identification methods depend on tagging according to function and not according to construction or form. For example, a differential pressure transmitter is not identified as a differential pressure transmitter
10、but as a: a) Flow transmitter when connected to an orifice plate when measuring flow. b) Level transmitter when connected to the side of a vessel when measuring liquid level. 2.6.3 The user is free to apply added identification by serial, equipment, unit, area, or plant number, or any other addition
11、al means required for the unique identification of a loop, instrument or function. 2.6.4 A unique function identification number shall be assigned to identify each: a) Loop instrument or device and its integral and/or inherent functions. ANSI/ISA-5.1-2009 - 16 - b) Loop-configurable function, which
12、requires or allows a unique user-assigned microprocessor or computer address. 2.7 Extent of symbolization 2.7.1 This standard provides symbol sets for the graphic depiction of a limited or total functionality of instruments and devices, entire monitor or control loops, or control circuits. 2.7.2 The
13、 amount of detail to be shown by the use of symbols depends on the purpose and audience for which the document is being prepared. 2.7.3 Sufficient symbols shall be used to show the functionality of the instrumentation and/or control loop being depicted; it is not considered necessary to provide a sy
14、mbol for each instrument device and each function required by a loop. 2.7.4 Additional construction, fabrication, installation, and operation details of an instrument are better described in a suitable specification, data sheet, loop diagram, installation/wiring drawing, or sketch, or other document
15、 intended for those requiring such details. 2.8 Inclusion and modification of this standard in User engineering and design documents 2.8.1 This standard may be used and, if used, shall be credited by a User/Owner in the preparation of engineering, design, or project standards, guidelines, and specif
16、ications, either without exception or with exception per the following: a) Without exception, in which case this standard in its entirety shall be mandatory with respect to: 1) Letters assigned a specific meaning in Table 4.1. 2) Symbols and their assigned meanings in Tables.5.1 through 5.8. 3) Symb
17、ol dimensions in Tables 6.1 through 6.8. b) With exceptions, in which case the parts of this standard for which exception is: 1) Taken shall be fully described and detailed in the User/Owner standards, guidelines, or specifications and in drawing cover sheet legends and notes. 2) Not taken shall be
18、mandatory. 2.8.2 Symbols different from those given in this standard and Users choice letters when used, shall be fully described and detailed in the User/Owners standards, guidelines, or specifications and in drawing cover sheet legends and notes. 2.8.3 A User must choose a numbering scheme, graphi
19、c symbol, and other choices where required, and document those choices. 2.8.4 When a previous issue of this standard is included by reference with or without exception in User/Owners engineering and design standards, guidelines or specifications, that standard in part or in its entirety shall be man
20、datory until such time as the User/Owners guidelines or standards are revised. - 17 - ANSI/ISA-5.1-2009 2.8.5 Symbols and the meanings of letters and symbols from previous versions of this standard that are different from those contained in this version may continue to be used provided they are clea
21、rly referenced in the Users engineering and design standards, practices, and/or guidelines. 3 Definitions 3.1 Definitions For the purposes of this standard, the following definitions apply. For additional information, see ISA-51.1-1979 (R 1993), “Process Instrumentation Terminology,” and ANSI/ISA-75
22、.05.01-2000 (R 2005), “Control Valve Terminology.” Terms italicized in a definition are themselves defined elsewhere in this clause. 3.1.1 accessible: a feature of a device or function, a feature of an interactive shared system function, or a feature that can be used or seen by an operator for the p
23、urpose of performing control operations, such as setpoint changes, auto-manual transfer, or on-off operations. 3.1.2 alarm: an indicating device or function that provides a visible and/or audible indication if and when the value of a measured or initiating variable is outside of set limits, has chan
24、ged from a safe to an unsafe condition, or has changed from a normal to an abnormal operating state or condition. a) actuation may be by a binary or analog device or function. b) indication may be by any or all of the following: annunciator panels, flashing lights, printers, buzzers, bells, horns, s
25、irens, or shared graphic display systems. 3.1.3 analog: a signal or device that has no discrete positions or states and changes value as its input changes value and when used in its simplest form, as in “analog signal“ as opposed to “binary signal”; the term denotes a continuously varying quantity.
26、3.1.4 application software: software specific to a user application that is configurable and in general contains logic sequences, permissive and limit expressions, control algorithms, and other code required to control the appropriate input, output, calculations, and decisions; see also software 3.1
27、.5 assignable: a system feature permitting channeling or directing of a signal from one device to another without the need for changes in wiring either by means of patching, switching, or via keyboard commands to the system. 3.1.6 auto-manual station: a manual loading station or control station that
28、 also provides switching between manual and automatic control modes of a control loop; see also manual station. ANSI/ISA-5.1-2009 - 18 - 3.1.7 balloon: an alternate term for the circular symbol used to denote and identify the purpose of an instrument or function that may contain a tag number; see pr
29、eferred term bubble. 3.1.8 basic process control system (BPCS): instrumentation and systems that are installed to monitor and control normal production operations using, but not limited to combinations of single-loop pneumatic and electronic monitors and controllers, programmable logic controllers a
30、nd distributed control systems. (a) A BPCS is necessary to operate a plant or process. 3.1.9 behind the panel: a location that in a broad sense means “not normally accessible to an operator,” such as the rear of an instrument or control panel, an enclosed instrument rack or cabinet, or an instrument
31、 rack room within an area that contains a panel. 3.1.10 binary: a signal or device that has only two discrete positions or states, and when used in its simplest form, as in “binary signal“ as opposed to “analog signal,“ the term denotes an “on-off“ or “high-low“ state. 3.1.11 board: a freestanding s
32、tructure consisting of one or more sections, cubicles, or consoles that has groups of discrete instruments mounted on it, houses the operator-process interface, and is chosen to have a unique designation; see panel. 3.1.12 bubble: the preferred term for the circle-based symbols used to denote and id
33、entify the purpose of an instrument or function that may contain a tag number; see alternate term balloon. 3.1.13 communication link: a wire, cable, or electromagnetic network or bus system that connects dedicated microprocessor-based and computer-based systems so that they share a common database,
34、and communicates according to a rigid protocol in a hierarchical and/or peer-to-peer relationship; see datalink. a) wire or cable networks may be twisted pair, coaxial, telephone, or fiber optic. b) electromagnetic networks may be radio or microwave. 3.1.14 computer control system: a system in which
35、 all control action takes place within a control computer, such as a mainframe computer or mini-computer, which may be single or redundant. 3.1.15 computing device: the preferred term for a device that performs one or more calculations or logic operations, or both, and transmits one or more resultan
36、t output signals; see also computing relay. - 19 - ANSI/ISA-5.1-2009 3.1.16 computing relay: an alternate term for a device that performs one or more calculations or logic operations, or both, and transmits one or more resultant output signals; see also computing device. 3.1.17 computing function: a
37、 hardware or software function that performs one or more calculations or logic operations, or both, and transmits one or more resultant output signals. 3.1.18 configurable: a term for devices or systems whose functional and/or communication characteristics can be selected or rearranged through setti
38、ng of program switches, application software, fill-in-the-blank forms, pull-down menus, entered values or text, and/or other methods, other than rewiring as a means of altering the configuration. 3.1.19 controller: a device having an output that varies to regulate a controlled variable in a specifie
39、d manner that may be a self-contained analog or digital instrument, or may be the equivalent of such an instrument in a shared-control system. a) an automatic controller varies its output automatically in response to a direct or indirect input of a measured process variable. b) a manual controller,
40、or manual loading station, varies its output in response to a manual adjustment; it is not dependent on a measured process variable. c) a controller may be an integral element of other functional elements of a control loop. 3.1.20 control station: a manual loading station that also provides switchin
41、g between manual and automatic control modes of a control loop; see also auto-manual station. a). the operator interface of a distributed control system may be referred to as a control station. 3.1.21 control valve: a device, other than a common, hand-actuated process block valve or self-actuated ch
42、eck valve, that directly manipulates the flow of one or more fluid process streams. a) the designation “hand control valve“ shall be limited to hand-actuated valves that when used for process throttling require identification as an instrument or control device. 3.1.22 converter: a device that receiv
43、es information as one form of an instrument signal and transmits an output signal as another form, such as a current-to-pneumatic signal converter. a). an instrument that changes a sensors output to a standard signal, is properly designated as a transmitter, not a converter; typically, a temperature
44、 element TE connects to a transmitter TT, not to a converter TY. ANSI/ISA-5.1-2009 - 20 - b) a converter is sometimes referred to as a transducer, a completely general term not recommended for signal conversion. 3.1.23 datalink: a wire, cable, or electromagnetic network or bus system that connects f
45、ield-located devices with dedicated microprocessors so that they share a common database and communicate according to a rigid protocol in a hierarchical and/or peer-to-peer relationship to other such devices and/or compatible microprocessor-based systems; see also communication link. a) wire or cabl
46、e networks may be twisted pair, coaxial, telephone, or fiber optic. b) electromagnetic networks may be radio or microwave. 3.1.24 detector: a device that is used to detect the presence of something, such as flammable or toxic gases or discrete parts; see also primary element and sensor. 3.1.25 devic
47、e: a piece of instrument hardware that is designed to perform a specific action or function, such as a controller, indicator, transmitter, annunciator, or control valve. 3.1.26 digital: a signal or device that generates or uses binary digit signals to represent continuous values or discrete states.
48、3.1.27 discrete instrument a device or hardware that has a separate entity, such as a single-case controller or recorder. 3.1.28 discrete signals: signals that have any number of non-continuous distinct or defined states or positions. a) Binary signals are a subset. 3.1.29 distributed control system
49、 (DCS): instrumentation, input/output devices, control devices and operator interface devices, which in addition to executing stated control and indication functions, also permit transmission of control, measurement, and operating information to and from single or multiple-user specifiable locations, connected by single or multiple communication links. 3.1.30 field instrument: an instrument that is not mounted on a panel or console or in a control room but commonly in the vicinity of its primary element or final control element; see local instrument. 3.1.31 final control element
