ISO-1966-1973.pdf

INTERNATIONAL STANDARD $ 1966 0 R 4Il! INTERNATIONAL ORGANIZATION FOR STANDARDlZATlON .MEXAYHAPOAHAR OP,-AHIISAUHR no CTAHAAPMALWII.ORGANISATION INTERNATIONALE DE NORMALISATION Crimped joints for aircraft electrical cables First edition - 1973-02-15 G UDC 629.7.064.5 : 621.315.68 Ref. No. IS0 1966-1973 (E) m 6 - Descriptors : aircraft, aircraft equipment, electrical cables, joints, mechanical crimping, specifications, tests. ii i Price based on 7 pages Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/25/2007 00:51:40 MDTNo reproduction or networking permitted without license from IHS -,-,- FOREWORD IS0 (the International Organization for Standardization) is a worldwide federation of national standards institutes (IS0 Member Bodies). The work of developing International Standards is carried out through IS0 Technical Committees. Every Member Body interested in a subject for which a Technical Committee has been set up has the right to be represented on that Committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the Technical Committees are circulated to the Member Bodies for approval before their acceptance as International Standards by the IS0 Council. International Standard IS0 1966 was drawn up by Technical Committee ISOKC 20, Aircraft and space vehicles. It was approved in May 1970 by the Member Bodies of the following countries : Belgium India Brazil Israel Canada Italy Czechoslovakia Japan Egypt, Arab Rep. of Netherlands Germany New Zealand Greece Romania South Africa, Rep. of Spain Switzerland Turkey United Kingdom U.S.S.R. The Member Bodies of the following countries expressed disapproval of the document on technical grounds : France U.S.A. 0 International Organization for Standardization, 1973 ? Printed in Switzerland Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/25/2007 00:51:40 MDTNo reproduction or networking permitted without license from IHS -,-,- INTERNATIONAL STANDARD IS0 1966-1973 (E) Crimped joints for aircraft electrical cables 1 SCOPE AND FIELD OF APPLICATION 1.1 This international Standard specifies the design requirements (and tests) for the crimping of insulated and non-insulated terminations to general purpose electrical cables for aircraft, with conductors of copper, copper alloy, aluminium or aluminium alloy, in locations in which the stabilized conductor temperature does not exceed the values specified for the relevant type of cable, i.e. 105 C, 190 C or 260 C. The type of cable with which the terminations are intended to be made has to be declared (see 3.1.5). 1.2 The international Standard also contains recommendations relating to the inspection of such connections and the tools used to perform the crimping operation. Since satisfactory crimping is dependent upon the maintenance and setting of tools it also contains recommendations for tests to confirm their serviceability. 1.3 Testing of crimped joints to assess their suitability for aircraft shows that certain environmental conditions, for example vibration, have no significant effect on the performance of the joints. It has therefore not been considered necessary to provide for such tests in this International Standard. 2.5 cable splice connection : A permanent connection formed by the ends of electrical cable conductors attached to a cable splice. 2.6 crimping: A method of firmly attaching a terminal end or cable splice to a conductor by re-shaping the barrel around the conductor to establish good electrical and mechanical contact. 2.7 insulation grip : That part of a terminal barrel or cable splice barrel into which the insulation of the cable is placed, and which by reforming grips the insulation. 2.8 pre-insulated joint: A crimped connection formed with an insulated terminal end or insulated cable splice. 2.9 post-insulated joint : An uninsulated crimped con- nection insulated after conductor crimping. 2.10 crimping tool: A manually operated or power-operated mechanical device for making a crimp or insulation grip. 2.11 positioner: A locator, turret or other device permanently or removably attached to a crimping tool, serving correctly to locate and control the position of the crimp on the barrel. 2 DEFINITIONS 3 DESIGN REQUIREMENTS 2.1 termination : A permanent connection formed by the end of an electrical cable conductor with a terminal end or a pin or socket contact. 2.2 terminal end : A connecting device with barrel(s) accommodating an electrical cable conductor with or without additional provision to accommodate and secure the insulation. 2.3 pin or socket contact: A contact used in a plug or socket (receptacle) with a barrel at one end to accommo- date an electrical cable conductor with or without ad- ditional provision to secure the insulation. 2.4 cable splice: A connecting device with barrel(s) each accommodating an electrical cable conductor(s) with or without additional provision to accommodate and secure the insulation. 3.1 General 3.1.1 Terminal ends, pin or socket contacts and cable splices shall comply with the requirements of the appropriate national and international standards. 3.1.2 The protective treatment and surface finish of the terminal end, pin or socket contact or cable splice shall be of such a quality that the completed crimped connection complies with the requirements of this International Standard. The electrochemical potential difference between all conducting surfaces should not exceed 0,25 V. 3.1.3 The design of the terminal end, pin or socket contact or cable splice shall be such that adequate engagement of the cable conductor in the completed joint can be readily established by inspection. 1 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/25/2007 00:51:40 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO1966-1973 (E) 3.1.4 Any material used for pre- or post-insulation shall be non-corrosive, resistant to abrasion, fungus and aircraft fluids and shall not support combustion. The insulation, and internal sleeve if any, shall remain firmly fixed in its correct position before and after crimping. The insulation should be colour-coded in respect of its conductor size or sizes in accordance with the relevant national standards. 3.1.5 The manufacturer shall make the following information available : 1) terminal end, pin or socket contact or cable splice material specification; 2) protective treatment; 3) size and type of cable for which each item is available; 4) appropriate crimping tool or die references and settings; 5) the identification code of crimp marking; 6) information on the crimping; 7) maximum overall crimp; 8) instruction sheets recommended crimping 3.2 Crimped joints preparation of cable ends before dimensions of the completed for the proper use of the tool. The completed crimped joint should take the form of a conductor crimp and insulation grip effected in one operation, using the die or dies stipulated by the tool manufacturer. All terminal ends or cable splices for size 12 cables or smaller shall have an insulation grip unless equivalent insulation support is otherwise provided. 3.3 Tools and dies 3.3.1 Tools shall be so designed that 1) they will correctly locate and control the position of the crimp; 2) they will not release the termination during normal operation until the crimp has been correctly formed; 3) they will not axially deform pin or socket contacts or increase the effective diameter along the length of the crimped section by more than the amount specified in the connector specification; 4) during the formation of the conductor crimp, they will apply the appropriate mark, where required by section 6, to indicate the die size or tool which has been used; 5) they will not adversely affect the external protective treatment or insulation during the crimping operation; 6) they will not fracture the terminal end or cause any rough or sharp edges. 2 3.3.2 Tools shall be marked with the manufacturer s name and serial number. Dies for a particular tool should be interchangeable with other tools of that type. If they are not interchangeable they shall be marked to identify the tool for which they are suitable. 3.3.3 The gauging method of tools and dies shall be declared, and provision may be made for the use of test gauges or test bars. 4 DIMENSIONS The overall dimensions of the completed joints shall comply with the requirements of the appropriate national and international standards. 5 STRENGTH AND PERFORMANCE The mechanical strength and electrical performance of the completed joints shall be such that they fulfil the requirements of this International Standard. 6 MARKING The completed joint shall, when practicable, be marked in accordance with the declared code for the identification of the size of the crimping tool or die. Such marking, which shall be applied during the formation of the crimp, may be embossed or indented. 7 TESTS The tests listed below should be in accordance with the relevant national specification for crimped joints for general purpose electrical cables for aircraft. Evidence should be available to the purchaser that joints covered by this International Standard have satisfactorily passed type tests conducted in accordance with section 8. In order that a consistent standard of quality be maintained, the manufacturer should conduct production control tests in accordance with section 9, and the user control tests in accordance with section 10. 8 TYPE TESTS 8.1 Test conditions Unless otherwise specified, all tests shall be performed at a temperature of 20 + 5 C, at an air pressure between 930 and 1 070 mbar and a relative humidity not greater than 80 %. All joints used in the type tests should be stored under these conditions for a period of 48 h before testing. 8.2 Test sequence and specimens 8.2.1 The tests in 8.3 to 8.7 shall be applied to each and every combination of type, size, material and finish of crimped conductor barrel, crimped to the appropriate sizes of conductor of each type, material and finish, by each type of tool and each size of die, indenter or positioner. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/25/2007 00:51:40 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 1966-1973 (E) 8.22 When a particular crimped conductor barrel is used on more than one item (for example on terminal ends and on pin and socket contacts, or cable splices), tests in accordance with 8.3 to 8.7 need only be carried out on one type of item. 8.2.3 When a particular crimped conductor barrel is designed to accommodate a range of conductor sizes, for a particular type of tool or type and size of die or positioner, tests need only be carried out on the smallest and largest sizes of conductors in the range. 8.2.4 When a particular tool, die or positioner is designed to accommodate a range of crimping barrels, tests need only be carried out on the largest and the smallest sizes of crimping barrels. 8.2.5 The tests shall be made in the order shown in Table 1 on sixteen specimens. If the tests in 8.5 and 8.6 are made consecutively on the same specimens, eight specimens only are necessary. TABLE 1 - Test sequence and number of specimens for tests in clauses 8.3 to 8.7 Clause Test Number of spec- imens for tests 8.3 8.4 8.5 8.6 8.4 8.7 Inspection Voltage drop Climatic Load and temperature cycling Voltage drop Tensile 1 to 16 1 to 16 lto 8 9to16 1 to 16 1 to 16 8.2.6 Specimens shall consist of 8.4.3 For the purposes of the test, the voltage drop across each joint shall be regarded as one-half of that ascertained by subtracting from the overall drop the voltage drop attributable to the length of included cable, i.e. 152 mm (6 in), measured on not less than 3 m (10 ft) of cable taken from the same reel as that used for the test specimens. 1) terminal ends : a length of cable with a terminal end at each end; 2) cable splices : lengths of cable joined by an in-line connector; For cables with copper or aluminium conductors the values of voltage drop so obtained shall not exceed the appropriate value listed in Table 2 or 3. For conductors other than copper or aluminium the voltage drop values should be as agreed with the approving authority. 3) pin or socket contacts : a length of cable with a pin or socket contact at each end. NOTE - Care should be taken that the conductor temperature remains sensibly constant for successive readings. The cables shall be 152 + 1,3 mm (6 + 0.05 in) long, measured before crimping between the points where the conductors enter the respective conductor crimping barrels. 8.5 Climatic test Specimens shall be numbered on an area not involved in the crimping operation. 8.5.1 The specimens shall be subjected to the tropical exposure test described in IS0 . . l) 8.2.7 The number of items to be tested in accordance with 8.8 and 8.10 shall be as stated in the appropriate clause. The attached cable may be of any suitable length. I) In preparation. 8.3 inspection The following shall be verified : 1) use of correct cable, tool, die and terminal end, pin and socket contact or cable splice; 2) correctness of dimensions; 3) correctness of form and location of crimp; 4) freedom from fracture, rough or sharp edges; 5) adequate insertion of conductor strands in the barrel; 6) absence of damage to the conductor or insulation; 7) correct die mark. 8.4 Voltage drop test 8.4.1 The appropriate test current stipulated in Table 2 or 3 at an open circuit voltage of not more than 30 V shall be passed through the specimen. For type tests, precision class measuring instruments shall be used. 8.4.2 For terminations other than pin or socket contacts the voltage drop shall be measured between the intersection of one palm and barrel and the corresponding point on the other terminal end, care being taken to avoid contact with the conductor strands. For pin or socket contacts the measurement shall be taken between the intersection of the shoulder and the crimped barrel of the pin or socket contacts. For cable splices, the measurement shall be between the midpoints of two consecutive connectors. (See Figure 1.) 8.5.2 Upon completion of the tests the specimen shall be examined and any visible signs of corrosion or other damage shall be reported to the approving authority. 3 Copyright International Organiza