1、BRITISH STANDARDBS EN 50396:2005Non electrical test methods for low voltage energy cables ICS 29.060.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36
2、g58+A1:2011National forewordThis British Standard is the UK implementation of EN 50396:2005+A1:2011. It supersedes BS EN 50396:2005, which is withdrawn.The start and finish of text introduced or altered by amendment is indicated in the text by tags. Tags indicating changes to CENELEC text carry the
3、number of the CENELEC amendment. For example, text altered by CENELEC amendment A1 is indicated by !“.The UK participation in its preparation was entrusted by Technical Committee GEL/20, Electric cables, to Subcommittee GEL/20/17 Electric Cables - Low voltage.A list of organizations represented on t
4、his subcommittee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations. BS EN 50396:2005+A
5、1:2011This British Standard waspublished under the authorityof the Standards Policy andStrategy Committeeon 14 November 2005 BSI 2011ISBN 978 0 580 67086 2Amendments/corrigenda issued since publicationDate Comments 31 October 2011 Implementation of CENELEC amendment A1:2011EUROPEAN STANDARD EN 50396
6、:2005+ A1NORME EUROPENNE EUROPISCHE NORM CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2005 CENELEC - All rights of exploitati
7、on in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 50396:2005 E ICS 29.060.20 Partially supersedes HD 21.2 S3:1997 + A1:2002 it is intended that they should be specified by the standard dealing with the relevant type of cable. Any test requirements which are given in
8、 this standard may be modified by the relevant cable standard to suit the needs of a particular type of cable. 4 General test methods for dimensions 4.1 Measurement of insulation thickness 4.1.1 Procedure The thickness of insulation shall be measured in accordance with 8.1 of EN 60811-1-1. Three sam
9、ples shall be taken from the cable; each sample shall be separated from the next by a distance of at least 1 m. Conformity shall be checked on each core. For multicore cables, except for the test in 4.1 , not more than three cores (of different colours, if available) shall be tested unless otherwise
10、 specified. ! “BS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E) 6 If withdrawal of the conductor is difficult, it shall be stretched in a tensile testing machine or the piece of core shall be loosened by stretching or some other suitable means that does not damage the insulation. The cores of flat
11、 non-sheathed cords shall not be separated. 4.1.2 Evaluation of results The mean of the 18 values (expressed in millimetres) obtained from the three pieces of insulation from each core shall be calculated to two decimal places and rounded off as given in Annex B, and this shall be taken as the mean
12、value of the thickness of insulation. The lowest of all values obtained shall be taken as the minimum thickness of insulation at any place. 4.2 Measurement of sheath thickness for circular cables 4.2.1 Procedure The thickness of the sheath for circular cables shall be measured in accordance with 8.2
13、 of EN 60811-1-1. One sample of cable shall be taken from each of three places, separated by at least 1 m. For flat cords the measurements shall be carried out in accordance with 4.3. 4.2.2 Evaluation of results The mean of all the values (expressed in millimetres) obtained from the three pieces of
14、sheath shall be calculated to two decimal places and rounded off as given in Annex B, and this shall be taken as the mean value of the thickness of sheath. The lowest of all values obtained shall be taken as the minimum thickness of sheath at any place. 4.3 Measurement of sheath thickness for flat c
15、ables 4.3.1 Measuring equipment A measuring microscope or a profile projector shall be used, each instrument being capable of at least 10 x magnification. The equipment shall have an accuracy of 0,01 mm. In cases of dispute a microscope allowing a reading with an accuracy of 0,01 mm or a profile pro
16、jector of at least 20 x magnification shall be used. 4.3.2 Preparation of test pieces One sample of cable shall be taken from each of three places, separated by at least 1 m. After all materials inside the sheath have been removed, a test piece shall be prepared from each sample by cutting with a su
17、itable device (sharp knife, razor blade, etc.) a slice of sheath along a plane perpendicular to the longitudinal axis of the cable. If the sheath carries an indented marking, the test piece shall be taken so as to include such marking. 4.3.3 Measuring procedure The test piece shall be placed under t
18、he measuring equipment with the plane of the cut perpendicular to the optical axis. Measurements shall be taken on lines approximately parallel to the minor axis and on the major axis of the cross section, at the position of each core, as shown in Figure 1. BS EN 50396:2005+A1:2011 EN 50396:2005+A1:
19、2011 (E) 7 The thinnest place on the sheath shall be measured. Where this does not coincide with one of the designated measurement points shown in Figure 1, it shall be substituted for the closest such point, to give a total of six measurements. The measurements shall be made in millimetres to two d
20、ecimal places. 4.3.4 Evaluation of results The mean of all the values (expressed in millimetres) obtained from the three pieces of sheath shall be calculated to two decimal places and rounded off as given in Annex B, and this shall be taken as the mean value of the thickness of sheath. The lowest of
21、 all values obtained shall be taken as the minimum thickness of sheath at any place. 1Key 1 minimum thickness Figure 1 - Measurement of sheath thickness (flat cable) 4.4 Measurement of overall dimensions and ovality 4.4.1 Overall dimensions 4.4.1.1 Procedure The measurement of the overall diameter o
22、f any circular cable and of the overall dimensions of flat cables with a major dimension not exceeding 15 mm shall be carried out in accordance with 8.3 of EN 60811-1-1. The three samples taken in accordance with 4.1.1, 4.2.1 or 4.3.2 shall be used. For the measurement of flat cables with a major di
23、mension exceeding 15 mm, a micrometer, a profile projector or similar equipment shall be used. 4.4.1.2 Evaluation of results The mean of the values obtained shall be taken as the mean overall dimensions. BS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E) 8 4.4.2 Procedure for ovality measurement For
24、 checking the ovality of circular sheathed cables, two measurements shall be made at the same cross-section of the cable, covering the maximum and minimum values. 5 Tests relating to marking and colouring 5.1 Durability The durability of printed marking or of colour shall be checked by trying to rem
25、ove the marking or colour by rubbing lightly 10 times with a piece of cotton wool or cloth soaked in water. 5.2 Green-and-yellow measurement 5.2.1 General This method is not appropriate where the colour marking forms a spiral on the insulation. 5.2.2 Procedure Two samples of the green-and-yellow cor
26、e each approximately 100 mm in length, shall be taken at least 2 m one from the other. Measure a 15 mm length from each of the samples and cut three sections of insulation from each 15 mm test piece length, one from each end and one from the centre. Project a 10 X minimum magnified image of each cro
27、ss section on to a ground glass screen and make a visual estimation of the colour boundaries at the outer surface of the core. Continue the measurement using either of the following methods. Method 1 Measure the distance d1 and the core diameter D (Figure 2a). Figure 2a - Measurement of the green-an
28、d-yellow proportion BS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E) 9 Calculate the value for sine using the formula: sin = Dd1d1 = the chord of the green segment. D = the mean value of the diameter calculated from three measurements at different angles Calculate the percentage (Gp) of green (or
29、yellow) using the following formula: 1003602=pG In order to facilitate the calculation, the table in Annex C can be used. Method 2 Measure to the nearest degree, using a protractor placed on the magnified image, the angle subtended at the centre of the cross section by each portion of green (or yell
30、ow if appropriate). See Figure 2b. Key 1 base colour 2 other colour Figure 2b - Measurement of the green-and-yellow proportion Calculate the percentage (Gp) of green (or yellow) for each cross section using the following equation: 100360=TpAG ATis the total sum of each of the angles of rotation thro
31、ugh each of the portions of green (or yellow if appropriate). 5.2.3 Evaluation of results Calculate the mean of the six measurements and round to the nearest integer. Compare the results with the requirement specified in the relevant cable standard. BS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E)
32、 10 6 Tests for mechanical strength of cables 6.1 Static flexibility test 6.1.1 Apparatus A sample with a length of (3 0,05) m shall be tested using test apparatus similar to that shown in Figure 3. Two clamps, A and B, shall be located at a height of at least 1,5 m above ground level. Clamp A shall
33、 be fixed and clamp B shall move horizontally at the level of clamp A. 6.1.2 Procedure Clamp the ends of the sample vertically so that they remain vertical during the test, one end in clamp A, the other in the movable clamp B which shall be at a distance L = 0,20 m from clamp A. NOTE The cable shoul
34、d take approximately the shape indicated by Figure 3 (dotted lines). Move the movable clamp B away from the fixed clamp A until the loop formed by the cable takes the shape, indicated in Figure 3 by the heavy outline, of the U enclosed wholly between two plumb lines through the clamps and set up tan
35、gentially to the external generatrix of the cable. Measure the new distance, L/. The cable shall then be turned in the clamps by 180, and the test repeated. Calculate the mean value of L/. 6.1.3 Pre-conditioning of non-conforming samples Where the cable does not satisfy the requirement for L/, or in
36、 the case of dispute, the test shall be repeated after the following pre-conditioning. Wind the sample four times on and off a reel with a diameter approximately 20 times the outer diameter of the cable. Each time the sample shall be turned through 90, for round cables or, in the case of flat cables
37、, through 180. After this pre-conditioning, the sample shall be subjected to the test described in 6.1.2. BS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E) 11 LL = 0,20 mB BAXX1,50 m11Key 1 plumb line Figure 3 - Static Flexibility Test 6.1.4 Requirements The requirements for the maximum distance of
38、 L/ shall be given in the relevant cable standard. BS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E) 12 6.2 Two pulley flexing test 6.2.1 General The applicability of this test is given in the relevant cable standard. NOTE Normally this test should not be applied to: - tinsel cords; - single core c
39、ables with flexible conductors for fixed wiring; - multi-core flexible cables having conductors of nominal cross-sectional area greater than 2,5 mm2for thermoplastic cables, or greater than 4 mm2for crosslinked cables; - cables having more than 18 cores laid up in more than two concentric layers. 6.
40、2.2 Apparatus This test shall be carried out by means of the apparatus shown Figure 4. This apparatus consists of a carrier C, a driving system for the carrier and four pulley wheels for each sample of cable to be tested. The carrier C supports two pulley wheels A and B, which are of the same diamet
41、er. The two fixed pulley wheels, at either end of the apparatus, may be of a different diameter from pulley wheels A and B, but all four pulley wheels shall be so arranged that the sample is horizontal between them. The carrier makes cycles of forward and backward movements over a distance of 1 m at
42、 an approximately constant speed of 0,33 m/s between each reversal of the direction of movement. The pulley wheels shall be made of metal. Pulley wheels with a semi-circular shaped groove shall be used for testing circular cables and pulley wheels with a flat groove for testing flat cables. The rest
43、raining clamps D shall be fixed so that the pull is always applied by the weight from which the carrier is moving away. The distance from one restraining clamp to its support, while the other clamp is resting on its support, shall be a maximum of 50 mm. The driving system shall be such that the carr
44、ier reverses smoothly and without jerks when it changes from one direction of movement to the other. 6.2.3 Sample preparation A sample of flexible cable about 5 m long shall be stretched over the pulley wheels, as shown in Figure 4, each end being loaded with a weight. The mass of this weight and th
45、e diameter of pulley wheels A and B shall be as given for the particular cable type (Table 1a for thermoplastic cables or Table 1b for crosslinked cables as appropriate). 6.2.4 Current loading of cores During the flexing test the cable sample shall be loaded with the current specified in Table 2a or
46、 Table 2b for the particular cable type as follows: - 2 core and 3 core cables: all cores shall be loaded fully - 4 core and 5 core cables: three cores shall be loaded fully or all cores shall be loaded with a current of Inamps, calculated according to the following formula: where n = number of core
47、s I3= full current according to the particular cable type n3I= I 3nBS EN 50396:2005+A1:2011 EN 50396:2005+A1:2011 (E) 13 The current loading shall be applied either through the electrical system used to apply the voltage between cores specified in 6.2.5, or through a separate current generator syste
48、m (e.g. current transformers). On cores which are not loaded, a signal current shall be applied. Cables having more than five cores shall not be loaded. 6.2.5 Voltage between cores For two-core cables and for light, sheathed three- and four-core cables, the voltage between the conductors shall be (2
49、30 15) V a.c. For all other cables having three or more cores, a three-phase a.c. voltage of 400 V 15% shall be applied to three conductors, any additional conductors being connected to the neutral. Three adjacent cores shall be tested; in the case of a multi-layer construction they shall be taken from the outer layer. 6.2.6 Fault detection The flexing apparatus shall be constructed so that it will detect and stop if any of the following occur during the flexing test: interruption of the test current; short circuit between the cores
