• BS CECC 25000:1977

    Withdrawn A Withdrawn Standard is one, which is removed from sale, and its unique number can no longer be used. The Standard can be withdrawn and not replaced, or it can be withdrawn and replaced by a Standard with a different number.

    Specification for harmonized system of quality assessment for electronic components: generic specification: inductor and transformer cores for telecommunications

    Available format(s):  Hardcopy, PDF

    Withdrawn date:  01-09-1998

    Language(s):  English

    Published date:  31-05-1977

    Publisher:  British Standards Institution

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    Table of Contents - (Show below) - (Hide below)

    Foreword
    Preface
    SECTION 1 - SCOPE
    SECTION 2 - GENERAL
    2.1 Order of precedence
    2.2 Related documents
    2.3 Units, symbols and terminology
    2.3.1 General
    2.3.2 Multiples and sub-multiples of units
    2.3.3 Letter symbols
    2.3.4 Type of core
    2.3.5 Inductance factor
    2.3.6 Variability
    2.3.7 Temperature factor
    2.3.8 Temperature coefficient
    2.3.9 Disaccommodation
    2.3.10 Disaccommodation coefficient
    2.3.11 Disaccommondation factor
    2.3.12 Magnetic conditioning
    2.3.13 Instability
    2.3.14 Instability factor
    2.3.15 Parallel reactance coefficient
    2.3.16 Parallel resistance coefficient
    2.3.17 Vanishingly low value of flux density
    2.4 Standard and preferred values
    2.4.1 Dimensions
    2.4.2 Inductance factor
    2.5 Effective parameters
    SECTION 3 - QUALITY ASSESSMENT PROCEDURES
    3.1 Primary stage of manufacture
    3.2 Specimen
    3.3 Inspection for qualification approval
    3.4 Quality conformance inspection
    3.5 Delayed delivery
    3.6 Certified test records
    SECTION 4 - TEST AND MEASUREMENT CONDITIONS
    4.1 Standard measuring frequencies
    4.2 Environmental conditions
    4.2.1 General
    4.2.2 Ambient temperature
    4.3 General precautions for methods involving
            permeability measurements
    4.3.1 Parameters involved
    4.3.2 Relation to practice
    4.3.3 Mounting of cores consisting of more than one
            part
    4.4 General precautions for loss measurement at low
            flux density
    4.4.1 Contributory losses
    4.4.2 Mounting
    4.5 Magnetic conditioning
    4.5.1 Object
    4.5.2 Principles of the methods
    4.5.3 Procedure for the electrical method
    4.5.4 Procedure for the thermal method
    4.6 Inductance measurement
    4.6.1 Object
    4.6.2 Means of coupling
    4.6.3 Absolute measurement
    4.6.4 Relative measurement
    4.7 Disaccommodation
    4.7.1 Object
    4.7.2 Principle of the method
    4.7.3 Specimens
    4.7.4 Timing device
    4.7.5 Measuring procedure
    4.7.6 Calculation
    4.8 Variation of permeability with temperature
    4.8.1 Object
    4.8.2 Principle of the method
    4.8.3 Specimens
    4.8.4 Temperature cycling device
    4.8.5 Timing device
    4.8.6 Measuring procedure
    4.8.7 Calculation
    4.9 Range of inductance adjustment
    4.9.1 Object
    4.9.2 Terminology
    4.9.3 Principle of the measurement
    4.9.4 Specimens
    4.9.5 Measuring procedure
    4.9.6 Calculation
    4.10 Losses at low flux density
    4.10.1 Object
    4.10.2 Specimens
    4.10.3 Means of coupling
    4.10.4 Measurement of residual plus eddy current loss
    4.10.5 Measurement of the hysteresis loss
    4.10.6 Reference methods
    4.11 Mechanical testing
    4.11.1 Compression load
    4.11.2 Adjusting device
    4.12 Third harmonic distortion
    4.12.1 Object
    4.12.2 Terminology
    4.12.3 Principle of the measurement
    4.12.4 Specimens
    4.12.5 Measuring instruments
    4.12.6 Measuring procedure
    4.12.7 Calculation
    4.13 Magnetic shock sensitivity
    4.13.1 Object
    4.13.2 Terminology
    4.13.3 Principle of the measurement
    4.13.4 Specimens
    4.13.5 Pulse generator
    4.13.6 Timing device
    4.13.7 Measuring procedure
    4.13.8 Calculation
    4.14 Contribution of the adjusting device to the core
            instability
    4.14.1 Object
    4.14.2 Terminology
    4.14.3 Principle of the method
    4.14.4 Specimens
    4.14.5 Conditioning chamber
    4.14.6 Measuring procedures
    4.14.7 Calculation
    4.15 Influence of a static magnetic field
    4.16 Total core loss
    4.16.1 Object
    4.16.2 Principles of measurement
    4.16.3 Specimens
    4.16.4 Measuring coil
    4.16.5 Measuring equipment
    4.16.6 Measuring procedure
    4.16.7 Calculation
    4.17 (Effective) Amplitude permeability
    4.17.1 Object
    4.17.2 Principle of measurement
    4.17.3 Specimens
    4.17.4 Measuring coil
    4.17.5 Measuring equipment
    4.17.6 Measuring procedure
    4.17.7 Calculation
    Appendices
    I. Damped oscillation method for loss measurement
            calibration
    II. Transmission method for loss measurement
            calibration
    III. Examples of circuits for the measuring total core
            loss
            (1) Multiplying voltmeter method
            (2) Bridge method
            (3) Oscilloscope method
            (4) Non-reactive resistance
    IV. Examples of circuits for the measurement of the
            (effective) amplitude permeability
            (1) Circuit using measuring coil with a single
                 winding
            (2) Circuit using a double wound measuring coil

    Abstract - (Show below) - (Hide below)

    Terminology and procedure applicable to the entire family of inductor and transformer cores for telecommunications.

    General Product Information - (Show below) - (Hide below)

    Committee EPL/51
    Development Note REPLACES BS 9630:1973
    Document Type Standard
    Publisher British Standards Institution
    Status Withdrawn
    Superseded By

    Standards Referenced By This Book - (Show below) - (Hide below)

    BS CECC 25300:1981 Harmonized system of quality assessment for electronic components: sectional specification: magnetic oxide cores for power applications
    BS 9720:1989 Specification for custom-built transformers and inductors of assessed quality: generic data and methods of test
    BS EN 125200:1993 Harmonized system of quality assessment for electronic components: sectional specification: magnetic oxide cores for linear transformers
    BS EN 125400:1993 Harmonized system of quality assessment for electronic components: sectional specification: adjusters used with magnetic oxide cores for use in inductors and tuned transformers
    BS EN 125500:1996 Harmonized system of quality assessment for electronic components. Sectional specification: magnetic oxide ring cores for interference suppression and low level signal transformer applications

    Standards Referencing This Book - (Show below) - (Hide below)

    IEC 60431:1983 Dimensions of square cores (RM-cores) made of magnetic oxides and associated parts
    IEC 60133:2000 Dimensions of pot-cores made of magnetic oxides and associated parts
    IEC 60367-1:1982 Cores for inductors and transformers for telecommunications. Part 1: Measuring methods
    CECC 00006 : 1981 BASIC SPECIFICATION: ENVIRONMENTAL TEST PROCEDURES
    CECC 00100 : 1988 BASIC RULES - TO BE USED IN CONNECTION WITH THE INTERNAL REGULATIONS OF THE FEN e.V
    IEC 60205:2016 Calculation of the effective parameters of magnetic piece parts
    IEC 60027-1:1992 Letters symbols to be used in electrical technology - Part 1: General
    IEC 60424:1973 Guide to the specification of limits for physical imperfections of parts made from magnetic oxides
    IEC 60410:1973 Sampling plans and procedures for inspection by attributes
    ISO 497:1973 Guide to the choice of series of preferred numbers and of series containing more rounded values of preferred numbers
    CECC 00007 : 1978 BASIC SPECIFICATION: SAMPLING PLANS AND PROCEDURES FOR INSPECTION BY ATTRIBUTES
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