1、BRITISH STANDARD BSCECC 42100:1978 Incorporating Amendment No.1 Harmonized system of quality assessment for electronic components Sectional specification Low voltage varistors primarily for telephony applications UDC621.316.82.027.2BSCECC42100:1978 This British Standard, having been prepared under t
2、he directionof the Electronic Components Standards Committee, was published underthe authority of the Executive Board on 29 December1978 BSI 08-1999 The following BSI references relate to the work on this standard: Committee reference ECL/4 Draft for comment75/26223 DC ISBN 0 580 10480 X Cooperating
3、 organizations The Electronic Components Standards Committee, under whose direction this British Standard was prepared, consists of representatives from the following Government department and scientific and industrial organizations: British Electrical and Allied Manufacturers Association (BEAMA) El
4、ectricity Supply Industry in England and Wales Electronic Components Industry Federation* Institution of Electronic and Radio Engineers Ministry of Defence* National Supervising Inspectorate* Post Office* Society of British Aerospace Companies Limited* Telecommunication Engineering and Manufacturing
5、 Association (TEMA)* Trades Union Congress The organizations marked with an asterisk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this British Standard: Electrical Research Association Electronic Engineering Association
6、Amendments issued since publication Amd. No. Date of issue Comments 3977 May 1982 Indicated by a sideline in the marginBSCECC42100:1978 BSI 08-1999 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword iii Text of CECC42100 1BSCECC42100:1978 ii BSI 08-1999 Nation
7、al foreword This British Standard has been prepared under the direction of the Electronic Components Standards Committee. It is identical with CENELEC Electronic Components Committee (CECC)42100 “Sectional specificationLow voltage varistors primarily for telephony application”. The1st Amendment to C
8、ECC42100 was implemented as Amendment No.1 to this British Standard. This standard is a harmonized specification within the CECC system. Terminology and conventions. The text of the CECC specification has been approved as suitable for publication, without deviation, as a British Standard. Some termi
9、nology and certain conventions are not identical with those used in British Standards; attention is especially drawn to the following. The comma has been used throughout as a decimal marker. In British Standards it is current practice to use a full point on the baseline as the decimal marker. Cross
10、references. The British Standard harmonized with CECC00100 is BSE9000 “General requirements for electronic components of assessed quality harmonized with the CENELEC Electronic Component Committee System”. For each of the following International Standards referred to in the text there is a correspon
11、ding British Standard; these are as listed below: Detail specification layout. In the event of conflict between the requirements of this British Standard and the provisions of BS E9000 the latter shall take precedence except that the front page layout shall be in accordance with the requirements of
12、BS9000 Circular Letter No.15dated August1977. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligati
13、ons. International Standard Corresponding British Standard CECC42000:1978 BS CECC42000:1978 Generic specification: Varistors (Identical) CECC00100:1974 BS E9000 General requirements for electronic components of assessed quality harmonized with the CENELEC Electronic Component Committee System Part1:
14、1977 Basic rules (Identical) IEC68 BS2011 Basic environmental testing procedures (Identical) Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theCECCtitle page, pages ii to iv, pages1 to 8 and a back cover. This standard has been updated (see copyright dat
15、e) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BSCECC42100:1978 ii BSI 08-1999 Contents Page Foreword iii Section 1. Scope 1 Section 2. Preferred characteristics, ratings and severities for environmental tests 1 2.1 Characteristic
16、s 1 2.2 Ratings 2 2.3 Severities for environmental tests 2 2.4 Derating 3 2.5 Information to be given in a detail specification 3 Section 3. Inspection 5 3.1 Formation of inspection lots 5 3.2 Test methods 5 3.3 Qualification approval 5 Appendix AFixed sample size qualification approval test schedul
17、e 6BSCECC42100:1978 BSI 08-1999 iii Foreword The CENELEC Electronic Components Committee (CECC) is composed of those member countries of the European Committee for Electrotechnical Standardization (CENELEC) who wish to take part in a harmonized System for electronic components of assessed quality. T
18、he object of the System is to facilitate international trade by the harmonization of specifications and quality assessment procedures for electronic components, and by the grant of an internationally recognized Mark, or Certificate, of Conformity. The components produced under the System are thereby
19、 accepted by all member countries without further testing. This document has been formally approved by the CECC, and has been prepared for those countries taking part in the System who wish to prepare and issue detail specifications for LOW VOLTAGE VARISTORS PRIMARILY FOR TELEPHONY APPLICATIONS. It
20、should be read in conjunction with document CECC00100: Basic Rules(1974). At the date of printing of this document, the member countries of the CECC are Belgium, Denmark, France, Germany, Ireland, Italy, the Netherlands, Norway, Sweden, Switzerland and the United Kingdom, and copies of it can be obt
21、ained from the National Committees of the CENELEC in these countries. Preface This sectional specification was prepared by CECC Working Group4:“Resistors”. This is one of a series of sectional specifications, all relating to the generic specification printed as CECC42000. In accordance with the requ
22、irements of document CECC00100, it is based, wherever possible, on the Recommendations of the International Electrotechnical Commission. The text of this sectional specification was circulated to the CECC for voting in the documents listed below and was ratified by the CECC for printing as a CECC Sp
23、ecification. Document Voting date Report on the Voting CECC (Secretariat) 378 November1975 CECC (Secretariat) 516 CECC (Secretariat) 530 November1976 CECC (Secretariat) 635 CECC (Secretariat) 531 November1976 CECC (Secretariat) 608 CECC (Secretariat) 676 March1978 CECC (Secretariat) 707iv blankBSCEC
24、C42100:1978 BSI 08-1999 1 Section 1. Scope 1 This sectional specification prescribes the preferred values for characteristics and ratings and also the inspection requirements for disc type low voltage varistors of assessed quality primarily for telephony application, having a rated dissipation of no
25、t more than2W and a reference voltage of not more than100V. It selects from the generic specification, CECC42000, the appropriate methods of test to be used in detail specifications derived from this specification. Associated with this specification are one or more blank detail specifications each r
26、eferenced by a CECC number. A blank detail specification which has been completed as specified in2.5 of this specification forms a detail specification. These detail specifications may be used for the granting of qualification approval to a varistor and for the performance of quality conformance ins
27、pection in accordance with the CECC System. Section 2. Preferred characteristics, ratings and severities for environmental tests 2.1 Characteristics The values prescribed in detail specifications shall preferably be selected from the following: 2.1.1 Climatic category The varistors covered by this d
28、ocument are classified into climatic categories according to the general rules given in the Appendix to IEC68-1. The standard severities for the cold, dry heat and damp heat, steady state, tests are within the following ranges: Values selected within these ranges shall be chosen from those listed in
29、 the relevant tests of IEC68-2. The severities for the cold and dry heat tests are the lower and upper category temperatures. For some varistors, these temperatures will occur between two of the preferred temperatures given in IEC68-2. In this case the nearest preferred temperature within the catego
30、ry temperature range of the varistors shall be chosen for this severity. 2.1.2 Temperature coefficient 2.1.2.1 Temperature coefficient of current (for types having a current at reference voltage U1004A) Temperature coefficient of current at the reference voltage 0,8%/ C. 2.1.2.2 Temperature coeffici
31、ent of voltage (for types having a current at reference voltage 1004A) Temperature coefficient of voltage at a current of1mA: 0,1%/ C. 2.1.3 Limits for change in current The standard limits for change in current in each of the tests are given below. Cold: Test A (IEC68-2-1) 10 to 55 C Dry heat: Test
32、 B (IEC68-2-2) +40 to +85 C Damp heat, steady state: Test C (IEC68-2-3) 4 to56days Title of test paragraph number (See NOTE1) Change in current (See NOTE2) Current at reference voltageU 1004A Current at reference voltage1004A 4.10.2 4.11 4.12 Resistance to soldering heat Robustness of terminations R
33、apid change of temperature 10% k404A C.1.1 Overload 15% C.1.3 Pulse endurance 20% 4.16 4.17 Climatic sequence Damp heat, steady state 30% NOTE 1The paragraph numbers refer to CECC42000. NOTE 2Percentage limits are given for application to materials of which silicon carbide is the prototype. Limits a
34、re given in microamperes for application to materials of which zinc oxide is the prototype.BSCECC42100:1978 2 BSI 08-1999 2.1.4 Reference voltage The reference voltages are 25; 32; 36; 40; 48; 50; 60; 63; 66; 80 and 100 V. The values which are underlined shall be used in future designs. 2.1.5 Maximu
35、m current at reference voltage The standard, values of maximum current are: 0,010,050,50,911,51,7359 and15mA. 2.1.6 Non-linearity (See2.2.6 and AppendixC.1.2 of CECC42000) 2.2 Ratings The values prescribed in detail specifications shall preferably be selected from the following: 2.2.1 Rated dissipat
36、ion The standard values of rated dissipation at25 C are: 0,10,20,5and1W. 2.2.2 Insulation resistance The standard limit for insulation resistance shall be10MA or, after damp heat testing,1MA. 2.3 Severities for environmental tests Test severities prescribed in detail specifications shall preferably
37、be selected from the following: 2.3.1 Soldering Test T (IEC68-2-20) 2.3.2 Shock Test Ea (IEC68-2-27) V max : The value of voltage under pulse conditions is given in the detail specification and should not exceed145V. Solderability : Solder bath method at230 10 C; or, Solder globule method, duration3
38、s max Resistance to soldering heat : Test T b(IEC68-2-20A) Method1A. Pulse shape : half sine Acceleration : 490m/s 2 Pulse duration : 11ms Severity : 3 successive shocks in any one direction per specimen. Separate specimens to be used for any one direction. Mounting : Normal mounting means, in such
39、a manner that there shall be no parasitic vibration.BSCECC42100:1978 BSI 08-1999 3 2.4 Derating One of the following derating curves shall be applied: 2.5 Information to be given in a detail specification The following information shall be given in each detail specification and the values quoted sha
40、ll preferably be selected from those given in this document. NOTEThe information given in2.5.1 to2.5.6 may, for convenience, be presented in tabular form.BSCECC42100:1978 4 BSI 08-1999 2.5.1 Style See2.2.3 of CECC42000 2.5.2 Reference voltage See2.1.4 2.5.3 Maximum current at reference voltage See2.
41、1.5 2.5.4 Non-linearity See2.1.6 2.5.5 Rated dissipation See2.2.1 2.5.6 Dimensions The numerical value, in millimetres, shall be given for such of the following dimensions as are applicable and it shall be stated which dimensions are suitable for gauging. The detail specification shall state such ot
42、her dimensional information as will adequately describe the varistor. 2.5.7 Climatic category See2.1.1 2.5.8 Temperature coefficient (of current, or of voltage) See2.1.2 2.5.9 Marking See2.4 of CECC42000 The varistor may be colour coded in a manner stated in the National Specification. (An alpha-num
43、eric code to indicate the style is under consideration). 2.5.10 Ordering information The detail specification shall indicate that the following information is required when ordering varistors: reference voltage maximum current at reference voltage number of the detail specification and style referen
44、ce 2.5.11 Additional information (not for inspection purposes) The detail specification may include information (which is not required to be verified by the inspection procedure), such as circuit diagrams, curves, drawings and notes needed for the clarification of the detail specification. Maximum b
45、ody diameter : D Maximum body thickness, including terminations of styles with wire terminations : W Diameter of wire terminations : d Length of wire terminations : l Distance between wire terminations : A Height of exposed segment of metallized face (for styles mounted by pressure contact) : HBSCEC
46、C42100:1978 BSI 08-1999 5 Section 3. Inspection 3.1 Formation of inspection lots An inspection lot shall consist of varistors of the same style. It should be representative of those extremes of maximum current at reference voltage which have been produced during the period. Where a lot is formed fro
47、m specimens of different termination variants, that lot shall contain an equal portion of each termination variant. 3.2 Test methods Test methods shall be selected from those given in CECC42000 or, failing that, shall be described in the detail specification. 3.3 Qualification approval When it is de
48、sired to obtain qualification approval by adopting the fixed sample size procedure (see3.3.3 of CECC42000), use shall be made of the following test schedule. The conditions of test and the performance requirements shall be identical to those prescribed for quality conformance inspection in the detai
49、l specification.BSCECC42100:1978 6 BSI 08-1999 Appendix A Fixed sample size qualification approval test schedule (See Note1) Clause Number and Test Conditions of Test Performance requirement Defectives permitted (See Note2) n c t GROUP O (Non-destructive) 56 + 4 2 2 4.2.1 4.2.2 4.2.3 4.3 Visual examination Marking Dimensions (gauging) Current at reference voltage Reference voltage: - V As in4.2.1. As in4.2.2 As in the detail specification I: k - mA GROUP 1 (Destructive) 8 1 3 C.1.2 Voltage under pulse conditions Peak current: (As specified i
