Specification Forms for Process Measurement and Control ...

1 Specification Forms forProcess Measurement andControl Instruments, PrimaryElements, and Control ValvesApproved 30 October 1981 ISA 20 1981 FormerlyISA S20 1981 STANDARDISA The Instrumentation,Systems, andAutomation Society TMCopyright 1981 by the Instrument Society of America. All rights reserved. Printed in the UnitedStates of America. No part of this publication may be reproduced, stored in a retrieval system, ortransmitted in any form or by any means (electronic, mechanical, photocopying, recording, orotherwise), without the prior written permission of the Alexander Box 12277 Research Triangle Park, North Carolina 27709 ISA-20-1981, Specification Forms for Process Measurement and Control Instruments, Primary Elements and Control ValvesISBN 0-87664-347-0 ISA-S20-19813 PrefaceThis Preface is included for information purposes and is not part of Standard has been prepared as a part of the service of the ISA toward a goal of uniformity in the field of instrumentation.

2 To be of real value this report should not be static, but should be subjected to periodic review. Toward this end the Society welcomes all comments and criticisms, and asks that they be addressed to the Standards and Practices Board Secretary, ISA, 67 Alexander Drive, Box 12277, Research Triangle Park, North Carolina 27709, Telephone (919) 549-8411, Fax (919) 549-8288, e-mail: document was prepared by the Subcommittee on Instrument Specification Forms ( ) and was originally published in 1956 under the direction of G. G. Gallagher of the Fluor Corporation. In 1961 additional Forms were published, prepared by Committee 8D-RP20 under the direction of W.

3 Carmack of the Fluor Corporation. This revision was prepared, with the supervision of the Chairman, R. E. Frey of Rohm and Haas Company, by the committee as listed COMMITTEENAMECOMPANYR. E. Frey (deceased) Rohm and Haas CompanyW. S. Buzzard Fisher and Porter CompanyJ. G. Converse Sun Oil CompanyG. F. Erk Sun Oil CompanyJ. Imber Atlantic Richfield CompanyR. D. Irwin Honeywell, F. Kremer E. I. duPont deNemours & Co., Leese Catalytic D. Prescott Moore Products CompanyA. Rosenthol Catalytic IncorporatedF. J. Ryan, Jr. Clifford B. Ives & Co., C. Thomas Clifford B. Ives & Co., assistance of those who aided in the preparation of this Standard, by their review of the draft and by offering suggestions toward its improvement, is gratefully acknowledged.

4 The following have reviewed the report and served as Board of Review:NAMECOMPANYC. B. Anderson Armstrong Cork CompanyW. A. Bajek UOP Process DivisionA. S. Bartholomew Reliance Electric CompanyC. S. Beard Bechtel CorporationJ. V. Becker National LoadO. K. Booth North American RockwellL. R. Brewer Koppers Company, M. Calabrese M. W. Kellogg CompanyF. I. Callisen C. F. Braun & CompanyC. P. Clark United Technology CenterG. T. Clawson Goddard Space Flight CenterR. Coel The Fluor CorporationL. Costea Hunt-Wesson FoodsW. G. Cozart Dow Chemical Company E. Csaky Dow Chemical Company J. W. Eby Honeywell, W. Fifer Proctor & GambleW.

5 Forsyth Honeywell, G. Gallagher The Fluor CorporationW. J. Greter Union Carbide CorporationH. P. Haas Philco-FordL. A. Haines Valter, G. Haines Allied Chemical CorporationW. Y. Harkins Tennessee Eastman CompanyE. J. Hayter Allied Chemical CorporationJ. E. Holland E. I. duPont deNemours & CompanyE. A. Houser Beckman InstrumentsP. Kindersley Kamyr Kipnis Instrumentation ConsultantC. D. Kolbe NASAW. B. Kostiw Stone & Webster Engineering CorporationE. R. Langston Stearns-Roger CorporationP. E. Larsen Dow Chemical CompanyB. G. Liptak Crawford & Russell, Loewe Sargent & LundyF. Maltby Drexelbrook Engineering CompanyC. A.

6 Master Philco-FordA. F. Marks Bechtel CorporationM. W. Marxen Dow Badische CompanyC. McCrain Monsanto CompanyR. T. Miller Brown & Root, E. Nurmi The Detroit Edison CompanyP. L. Pettersen Lockheed Missile & Space CompanyE. Podolak Federal Aviation AdministrationC. Pray Brown & Root, D. Preszler Johnson Service CompanyC. A. Prior E. I. duPont deNemours & CompanyG. R. Rauschenberg IBM CorporationJ. Rellford Honeywell, A. Richards General ElectricE. J. Rogers Bourns Life SystemsD. E. Sanchez Jensen Instrument CompanyISA-S20-19815R. H. Schipper Jordan ValveK. D. Smith General Electric CompanyE. F. Spalidoro Barton SalesW.

7 Speight Honeywell Controls, L. Thoma Wyandotte Chemicals CorporationD. J. Untener Standard Oil CompanyW. C. Voyles Cummins Engine Company, Walsh, Jr. Eastman Kodak CompanyN. S. Waner Hallikainen InstrumentsJ. P. Wolfinger Alpha Portland Cement CompanyN. R. Zeller Tucson Gas & Electric CompanyR. Zielski Georgia-Pacific CorporationThis Standard was approved for publication by the Standards and Practices Board on July 15, B. Miller, Vice President Moore Products CompanyR. G. Hand, Secretary ISAP. Bliss Pratt Whitney Aircraft CompanyL. N. Combs retired from E. I. duPont deNemours & CompanyB. A. Christensen Continental Oil CompanyR.

8 L. Galley Bechtel CorporationT. J. Harrison IBM CorporationT. S. Imsland Fisher Controls CompanyP. S. Lederer National Bureau of StandardsE. C. Magison Honeywell, R. Mahoney IBM CorporationR. L. Martin Tex-A-Mation Engineering, G. Marvin Dow Chemical CompanyA. P. McCauley Glidden Durkee Div. SCM CorporationT. A. Murphy The Fluor Corporation, L. Nickens Reynold Metals CompanyG. Platt Bechtel CorporationA. T. Upfold Polysar A. Whitman Allied Chemical CorporationISA-S20-19817 Contents1 Purpose ..92 Scope ..93 Receiver instruments ..124 Annunciators ..165 Potentiometer instruments Specification sheet instructions.

9 236 Temperature instruments (filled systems) ..277 Thermocouples and thermowells ..318 Resistance temperature sensors ..349 Bi-metal thermometers ..3710 Differential pressure instruments ..4011 Orifice plates and flanges ..4312 Rotameters ..4613 Magnetic flowmeters ..4914 Turbine flowmeters ..5215 Positive displacement meters ..5516 Level instruments (displacer or float) ..5817 Level instruments, capacitance type ..6118 Gage glasses and cocks ..6419 Traps and drainers ..6620 Pressure instruments ..7021 Pressure gages ..7422 Pressure switches ..7723 Instructions for Control valve data sheet ISA Form , Rev.

10 1 ..7924 Pressure Control valves pilots & regulators ..8425 Self-actuated temperature regulators ..8726 Pressure relief valves ..9127 Rupture discs ..9428 Solenoid valves ..96 ISA-S20-198191 The purpose of this standard is to promote uniformity in instrument specifications, both in content and form. Because of the complexity of present day instruments and controls it is desirable to have some type of Specification form to list pertinent details for use by all interested parties. General use of these Forms by users and manufacturers offers many advantages, as listed below:1)Assists in preparation of complete Specification by listing and providing space for all principal descriptive )Promotes uniform terminology*.