COMPLETE REVISION April 2013 Process Industry Practices Electrical PIP ELEMT01 Guidelines for Selecting IEEE and API Standards for AC Motors 250 HP (185 kw) and Larger
PURPOSE AND USE OF PROCESS INDUSTRY PRACTICES In an effort to minimize the cost of process industry facilities, this Practice has been prepared from the technical requirements in the existing standards of major industrial users, contractors, or standards organizations. By harmonizing these technical requirements into a single set of Practices, administrative, application, and engineering costs to both the purchaser and the manufacturer should be reduced. While this Practice is expected to incorporate the majority of requirements of most users, individual applications may involve requirements that will be appended to and take precedence over this Practice. Determinations concerning fitness for purpose and particular matters or application of the Practice to particular project or engineering situations should not be made solely on information contained in these materials. The use of trade names from time to time should not be viewed as an expression of preference but rather recognized as normal usage in the trade. Other brands having the same specifications are equally correct and may be substituted for those named. All Practices or guidelines are intended to be consistent with applicable laws and regulations including OSHA requirements. To the extent these Practices or guidelines should conflict with OSHA or other applicable laws or regulations, such laws or regulations must be followed. Consult an appropriate professional before applying or acting on any material contained in or suggested by the Practice. This Practice is subject to revision at any time. Process Industry Practices (PIP), Construction Industry Institute, The University of Texas at Austin, 3925 West Braker Lane (R4500), Austin, Texas 78759. PIP Member Companies and Subscribers may copy this Practice for their internal use. Changes or modifications of any kind are not permitted within any PIP Practice without the express written authorization of PIP. Authorized Users may attach addenda or overlays to clearly indicate modifications or exceptions to specific sections of PIP Practices. Authorized Users may provide their clients, suppliers and contractors with copies of the Practice solely for Authorized Users purposes. These purposes include but are not limited to the procurement process (e.g., as attachments to requests for quotation/ purchase orders or requests for proposals/contracts) and preparation and issue of design engineering deliverables for use on a specific project by Authorized User s client. PIP s copyright notices must be clearly indicated and unequivocally incorporated in documents where an Authorized User desires to provide any third party with copies of the Practice. PUBLISHING HISTORY July 2007 April 2013 Issued Complete Revision Not printed with State funds
COMPLETE REVISION April 2013 Process Industry Practices Electrical PIP ELEMT01 Guidelines for Selecting IEEE and API Standards for AC Motors 250 HP (185 kw) and Larger Table of Contents 1. Introduction... 2 1.1 Purpose... 2 1.2 Scope... 2 2. References... 2 2.1 Process Industry Practices... 2 2.2 Industry Codes and Standards... 2 3. General Guidelines... 3 4. IEEE 841... 3 5. API 541... 3 6. API 546... 4 7. API 547... 4 8. Data Sheets... 4 Process Industry Practices Page 1 of 4
PIP ELEMT01 COMPLETE REVISION Guidelines for Selecting IEEE and API Standards for AC Motors 250 HP (185 kw) and Larger April 2013 1. Introduction 1.1 Purpose This Practice provides guidelines for selecting Institute of Electrical and Electronic Engineers (IEEE) and American Petroleum Institute (API) standards for 250 hp (185 kw) and larger AC squirrel-cage induction motors and synchronous motors. 1.2 Scope 2. References This Practice provides guidance for selecting Institute of Electrical and Electronic Engineers (IEEE) and API standards for design, fabrication, inspection, testing, shipment, and documentation of 250 hp (185 kw) and larger AC squirrel-cage induction motors and synchronous motors. Applicable parts of the following Practices and industry codes and standards shall be considered an integral part of this Practice. The edition in effect on the date of contract award shall be used, except as otherwise noted. Short titles are used herein where appropriate. 2.1 Process Industry Practices (PIP) PIP ELSMT01D - Data Sheet for AC Squirrel Cage Induction Motor Specification (600 Volts and Below) 2.2 Industry Codes and Standards American Petroleum Institute (API) API 541 - Form-Wound Squirrel-Cage Induction Motors - 500 Horsepower and Larger API 546 - Brushless Synchronous Machines - 500 kva and Larger API 547 - General-Purpose Form-Wound Squirrel Cage Induction Motors - 250 Horsepower and Larger Institute of Electrical and Electronic Engineers (IEEE) IEEE 100 - The Authoritative Dictionary of IEEE Standard Terms IEEE 841 - IEEE Standard for Petroleum and Chemical Industry Premium - Efficiency Severe Duty, Totally Enclosed Fan-Cooled (TEFC) Squirrel Cage Induction Motors - up to and including 370 kw (500 hp) National Electrical Manufacturers Association (NEMA) MG 1 - Motors and Generators Process Industry Practices Page 2 of 4
PIP ELEMT01 COMPLETE REVISION Guidelines for Selecting IEEE and API Standards for AC Motors 250 HP (185 kw) and Larger April 2013 3. General Guidelines General application guidelines for selecting a standard for AC induction motors 250 hp (185 kw) and larger can be summarized by the following table. Table 1 Application Guidelines for Each Standard Application IEEE 841 API 547 API 541 API 546 Coupled loads Belted loads Axial loads Non Recip Compressors Reciprocating Compressors Centrifugal pumps Vertical turbine pumps Fans & blowers Induction generator Division 2 (Zone 2) Adjustable speed (ASD) 4. IEEE 841 IEEE 841 should be applied to squirrel cage induction motors, up to and including 500 hp (375 kw), in NEMA frame size, for general-purpose and industrial severe duty applications for the following cases (excluded from the scope of this standard are motors with sleeve bearings and additional specific features required for explosion-proof motors): a. Two-pole and slower TEFC or TENV motors 250 hp through 500 hp b. Drive centrifugal loads c. Drive loads having inertia values within those listed in NEMA MG 1 Part 20 d. Motors that are not induction generators e. Drive belted loads f. Drive axial loads g. Drive vertical pumps h. Motors in Adjustable Speed Drive service 5. API 541 API 541 should be applied to form-wound squirrel-cage induction motors 500 hp (375 kw) and larger that have one or more of the following characteristics: a. Is in critical service. IEEE 100 defines Critical Loads as Devices and equipment whose failure to operate satisfactorily jeopardizes the heath or safety of personnel, and/or results in loss of function, financial loss, or damage to property deemed critical by the user. This definition can provide guidance in determining motors which are in critical service. Process Industry Practices Page 3 of 4
PIP ELEMT01 COMPLETE REVISION Guidelines for Selecting IEEE and API Standards for AC Motors 250 HP (185 kw) and Larger April 2013 b. Is larger than 3000 hp (2250 kw) for speeds 1800 rpm and less c. Is rated 800 hp (600 kw) or greater for two-pole (i.e., 3000 and 3600 rpm) machines of totally-enclosed construction d. Is rated 1250 hp (930 kw) or greater for two-pole machines of open or guarded construction including machines with WP-I or WP-II type enclosures e. Driving a high-inertia load greater than the load Wk2 listed in NEMA MG-1 Part 20 f. Uses an adjustable speed drive as a source of power g. Is an induction generator h. Is a vertical machine rated 500 hp (375 kw) or greater i. Operates in an abnormally hostile environment 6. API 546 API 546 should be applied to form-wound and bar-wound brushless synchronous machines. The standard includes synchronous motors and generators with two different rotor designs. a. Salient-pole type rotor with solid or laminated poles b. Cylindrical type rotor with solid or laminated construction 7. API 547 API 547 should be applied to form-wound squirrel-cage induction motors for general-purpose and industrial severe duty applications for the following cases: a. Are rated 250 hp (185 kw) through 3000 hp (2250 kw) for four-, six-, and eight-pole speeds b. Are rated less than 800 hp (600 kw) for two-pole (i.e., 3000 and 3600 rpm) motors of totally-enclosed construction c. Are rated less than 1250 hp (930 kw) for two-pole motors of WP II type enclosures d. Driving centrifugal loads e. Driving loads having inertia values within those listed in NEMA MG 1 Part 20 f. Are not induction generators 8. Data Sheets 8.1 IEEE 841 8.1.1 For motors covered by the IEEE 841 specification, the purchaser s PIP ELSMT01D data sheet should be completed in order to completely inform the motor manufacture of the requirements. 8.2 API 541, 546, or 547 8.2.1 The API data sheets associated with the API standards referenced in this Practice should be completed in order to completely inform the motor manufacturer of the requirements. 8.2.2 The API standards include appendixes that provide guidance for making data sheet selections. Process Industry Practices Page 4 of 4