ANSI NEMA C12.10-2011 Physical Aspects of Watthour Meters - Safety Standard.pdf

1、NEMA Standards PublicationNational Electrical Manufacturers Association$16, their existence does not in any respect preclude anyone, whether he has approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. Th

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7、 United States of America. ANSI C12.10-2011 iv This page intentionally left blank. ANSI C12.10-2011 1 Table of Contents Page 1 SCOPE 5 2 REFERENCES 5 3 STANDARDS APPLICABLE TO WATTHOUR METERS 5 3.1 MOUNTING 5 3.2 VOLTAGE AND FREQUENCY . 5 3.3 CURRENT CLASSES AND TEST AMPERES (TA) 5 3.4 TYPICAL FORM

8、DESIGNATIONS 5 3.5 ROTOR (ELECTROMECHANICAL METERS ONLY) (SEE FIGURE 2) 7 3.6 CALIBRATION ADJUSTMENTS (ELECTROMECHANICAL METERS ONLY) . 8 3.8 DISPLAYS 10 3.9 REQUIREMENTS FOR SOLID-STATE REGISTERS 11 4 REQUIREMENTS APPLICABLE TO DETACHABLE WATTHOUR METERS . 12 4.1 DIMENSIONS 12 4.2 HANGER 12 4.3 SEA

9、LING 12 4.4 CONNECTIONS . 12 5 REQUIREMENTS APPLICABLE TO BOTTOM-CONNECTED METERS. 13 5.1 DIMENSIONS 13 5.2 HANGER 13 5.3 SEALING 13 5.4 CONNECTIONS . 13 5.5 TERMINAL BLOCKS . 13 5.6 TERMINALS 13 6 PROCEDURE FOR ASSIGNING FORM DESIGNATIONS . 14 A.1 FOREWORD TO FIRST EDITION (1978) . 37 A.2 FOREWORD

10、FROM THE SECOND EDITION (1987) 38 A.3 FOREWORD TO THIRD EDITION (1997) 39 A.4 FOREWORD TO FOURTH EDITION (2004) 40 ANSI C12.10-2011 2 Table of Figures Figure 1 External View of ANSI Type 2 Optical Port . 15 Figure 2 Markings for Watthour Meter Rotors . 16 Figure 3 Envelope of Surfaces that Project i

11、nto Socket for 4- to 6- Terminal Meters . 17 Figure 4 Envelope of Surfaces that Project into Socket 18 for 5-Terminal Meters in 7-Terminal Sockets 18 Figure 5 Envelope of Surfaces that Project into Socket for 7-Terminal and 8-Terminal Meters . 19 Figure 6 Envelope of Surfaces that Project into Socke

12、t 20 for 8-Terminal and 13- to 15-Terminal Meters 20 Figure 7 Mounting and Terminal Dimensions for Detachable Single Element and Multi-Element Watthour Meters with 4- to 8-Terminals 21 Figure 7A Suggested Dimensions for Bevels for Terminal Blades . 22 Figure 8 Mounting and Terminal Dimensions for De

13、tachable Multi-Element Watthour Meters 23 with 8-Terminals and 13- to 15-Terminals 23 Figure 9 Envelope of Round Covers for Detachable Single Element . 24 and Multi-Element Watthour Meters . 24 Figure 10 Internal Connections for Detachable Single Element Watthour Meters (front views) . 25 Figure 11

14、Internal Connections for Transformer Rated Detachable Multi-Element Watthour Meters 26 (front views) . 26 Figure 11A - Internal Connections for Transformer Rated Detachable Multi-Element Watthour Meters (front views) . 27 Figure 12 Internal Connections for Self-Contained Detachable Multi-Element Wat

15、thour Meters (front views) 28 Figure 12A 2-Element, 4-Wire (Universal) form 28S 29 Figure 13 Socket Jaw Position Identification (front view of socket) 30 Figure 14 Outline and Terminal Dimensions for Bottom-Connected Single Element Watthour Meters . 31 Figure 15 Outline and Mounting Dimensions for B

16、ottom-Connected Multi-Element Watthour Meters 32 Figure 16 Internal Connections for Bottom-Connected Single Element . 33 watthour meters (front views) 33 Figure 17 Internal Connections for Transformers Rated Bottom-Connected Multi-Element Watthour Meters (front views) . 34 Figure 18 Internal Connect

17、ions for Self-Contained Bottom-Connected Multi-Element Watthour Meters (front views) . 35 ANSI C12.10-2011 3 Foreword (This Foreword is not part of American National Standard C12.10-2010) There were relatively few changes made to this edition to bring it up to date with modern practice and with new

18、editions of other ANSI C12 standards. To this edition Form 32S was added. Also the text was revised to allow disconnect links to be optional. There were minor changes to some of the figures to make them easier to read. Dimensions and other relevant specifications given in this standard have been coo

19、rdinated with the American National Standard Requirements for Watthour Meters Sockets, ANSI C12.7- 2005. The Secretariat of the Accredited Standards Committee on Electricity Metering, C12, is held by the National Electrical Manufacturers Association (NEMA) and the National Institute of Standards and

20、 Technology. At the time the committee approved this standard, the C12 Committee had the following members: Tom Nelson, Chairman Paul Orr, Secretary Organization Represented Name of Representative Georgia Power Co. Larry Barto Itron, Inc. Brent Cain GE Energy Curt Crittenden Florda Power K (common),

21、 Y, and Z shall be used for three-wire contacts. ANSI C12.10-2011 13 5 Requirements Applicable to Bottom-Connected Meters 5.1 Dimensions Dimensions to assure mounting and connecting interchangeability are shown in Figures 14 and 15. 5.2 Hanger A hanging device shall be provided on the back of the ba

22、se. 5.3 Sealing 5.3.1 Meters shall be provided with facilities for sealing as shown in Figures 14 and 15. 5.3.2 The meter cover shall be provided with separate sealing facilities to seal the cover to the base, the demand reset lever, and battery access port (when applicable). 5.3.3 The terminal cove

23、r seal shall seal both the terminal cover and the meter cover. 5.4 Connections 5.4.1 The terminal arrangement and internal connections shall be as indicated in Figures 16 through 18. For external connections, refer to reference (3), The Handbook for Electricity Metering. 5.4.2 When pulse initiator c

24、ontact terminals are provided, they shall be located and may be identified as shown in Figures 17 and 18. K and Z shall be used for two-wire contacts; K (common), Y, and Z shall be used for three-wire contacts. 5.5 Terminal Blocks Terminal blocks shall be of arc-resistant material. 5.6 Terminals 5.6

25、.1 Current Terminals The current terminals shall accommodate the following wire sizes: 1) Self-contained meters: from 14 to 2 AWG, inclusive 2) Transformer-rated meters: from 14 to 4 AWG, inclusive 5.6.2 Voltage Terminals 1) The voltage terminals of single-element meters shall accommodate wire sizes

26、 from 14 to 10 AWG, inclusive. 2) The voltage terminals of multi-element meters shall accommodate wire sizes from 14 to 6 AWG, inclusive. 5.6.2.1 Grounding Terminal Grounding the exposed metal base of the meter shall be possible by one of the following methods: 1) A #10-32 tapped hole shall be provi

27、ded on the front, lower right corner of the base (see Figure 15 for the location). A #10-32 binding or washer head screw shall be provided in the tapped hole. 2) As an option, an untapped 3/16 in. hole entering the base from the right side and intersecting with the tapped hole may be provided. 3) Gr

28、ounding terminal not required for non-conductive bases. ANSI C12.10-2011 14 6 Procedure for Assigning Form Designations The form designation system denotes the circuit arrangement to which the meter is applicable, with due consideration given to the variations in terminal arrangement and wiring. The

29、 purpose is to provide a system of meter nomenclature that will assist in the selection and installation of equivalent meters, independent of the make of the meter and of successive types of the same manufacturer. Each form designation corresponds to an internal connection diagram in this publicatio

30、n and in The Handbook for Electricity Metering, reference 3, and is recorded at the National Electrical Manufacturers Association (NEMA). The suffix “A“ or “S“ in the form designation refers to bottom-connected or detachable meters, respectively. Though the form designation relates to the wiring and

31、 terminal arrangement, it does not change with current or voltage ratings, the number of voltage disconnects used, or the addition of auxiliariessuch as demand indicators, detents, voltage indicators, pulse sending devicesand the like. Test link(s) can be included or not on any form that shows links

32、 without a change in the form number. When a new variety of meter should be assigned a new form designation, a request for the assignment designation is filed with the Secretary of the Technical Committee of the NEMA Electricity Equipment Section, NEMA Headquarters, 1300 North 17th Street, Suite 184

33、7, Rosslyn, VA 22209. The Secretary of the NEMA Technical Committee shall assign the form designation, and advise the Accredited Standards Committee, C12. Upon counsel of this committee, the assigned new designation shall be considered approved. ANSI C12.10-2011 15 Figure 1 External view of ANSI typ

34、e 2 optical port .992.984DIA.1.55 DIA. MIN. CLEARANCEFOR MATING DEVICE.280/.244 SYMMETRICALMOUNTINGSURFACE.835.825DIA. (TRANSMITTER TRANSMISSION PATH).205.175DIA. (RECEIVER TRANSMISSION PATH).205.175.160 MIN.OPTICALREFERENCEPLANEOPTICALPATHFront View Side ViewCLCLNOTE: All dimensions are in inches.A

35、NSI C12.10-2011 16 302010908070605040INDEX MARKFigure 2 Markings for watthour meter rotors ANSI C12.10-2011 17 Figure 3 Envelope of surfaces that project into socket for 4- to 6- terminal meters Note 1: All dimensions are in inches. Unless otherwise specified, tolerances shall be 0.016 inch on singl

36、e dimensions and 0.031 inch on cumulative dimensions. Note 2: Symmetry should be assumed on dimensions from centerlines unless otherwise specified. Note 3: For 5-terminal meters for use in 7-terminal socket, see Figure 4. ANSI C12.10-2011 18 Figure 4 Envelope of surfaces that project into socket for

37、 5-terminal meters in 7-terminal sockets Note 1: All dimensions are in inches. Unless otherwise specified, tolerances shall be 0.016 inch on single dimensions and 0.031 inch on cumulative dimensions. Note 2: Symmetry should be assumed on dimensions from centerlines unless otherwise specified.ANSI C1

38、2.10-2011 19 Figure 5 Envelope of surfaces that project into socket for 7-terminal and 8-terminal meters Note 1: All dimensions are in inches. . Unless otherwise specified, tolerances shall be 0.016 inch on single dimensions and 0.031 inch on cumulative dimensions. Note 2: Symmetry should be assumed

39、 on dimensions from centerlines unless otherwise specified.ANSI C12.10-2011 20 Figure 6 Envelope of surfaces that project into socket for 8-terminal and 13- to 15-terminal meters Note 1: All dimensions are in inches. . Unless otherwise specified, tolerances shall be 0.016 inch on single dimensions a

40、nd 0.031 inch on cumulative dimensions. Note 2: Symmetry should be assumed on dimensions from centerlines unless otherwise specified. ANSI C12.10-2011 21 Figure 7 Mounting and terminal dimensions for detachable single element and multi-element watthour meters with 4- to 8-terminals Note 1: Grounding

41、 straps of surge gaps shall fall within the angle shown and be of sufficient length to provide contact surfaces from the minimum to the maximum radii. (Grounding means in the socket shall extend over the full angle shown and be located anywhere between the radii units). Note 2: All dimensions are in

42、 inches. . Unless otherwise specified, tolerances shall be 0.016 inch on single dimensions and 0.031 inch on cumulative dimensions. Note 3: Symmetry should be assumed on dimensions from centerlines unless otherwise specified. Note 4: Refer to Figure 13 for terminal sizes and placement. Note 5: Dimen

43、sions for size D terminals are suggested. ANSI C12.10-2011 22 Figure 7A Suggested dimensions for bevels for terminal blades ANSI C12.10-2011 23 Figure 8 Mounting and terminal dimensions for detachable multi-element watthour meters with 8-terminals and 13- to 15-terminals Note: 1. Grounding straps of

44、 surge gaps shall fall within the angle shown and be of sufficient length to provide contact surfaces from the minimum to the maximum radii. (Grounding means in the socket shall extend over the full angle shown and be located anywhere between the radii units). Note 2: All dimensions are in inches. .

45、 Unless otherwise specified, tolerances shall be 0.016 inch on single dimensions and 0.031 inch on cumulative dimensions. Note 3: Symmetry should be assumed on dimensions from centerlines unless otherwise specified. Note 4: Refer to figure 13 for terminal sizes and placement.ANSI C12.10-2011 24 Figu

46、re 9 Envelope of round covers for detachable single element and multi-element watthour meters Note 1: Prior to 1965 some meter covers had a minimum OD as low as 6.087 inches. Note 2: For socket and sealing ring dimensions refer to ANSI C12.7. Note 3: All dimensions are in inches.ANSI C12.10-2011 25 Form 1S 2-Wire Form 2S 3-Wire Form 3S 2-Wire Form 4S 3-Wire Figure 10 Internal connections for detachable single element watthour meters (front views)