1、DRAFT FOR DEVELOPMENT DD ENV 50232:1997 Aeronautical ground lighting electrical installation Isolating transformer: Equipment specifications and tests ICS 93.120DDENV50232:1997 This Draft for Development, having been prepared under the direction of the Electrotechnical Sector Board, was published un
2、der the authority of the Standards Board and comes into effect on 15 September 1997 BSI 03-1999 ISBN 0 580 27798 4 National foreword This publication is not to be regarded as a British Standard. It is being issued in the Draft for Development series of publications and is of a provisional nature bec
3、ause it is an interim draft. A revised version of this document is being produced by IEC/TC97. It should be applied on this provisional basis, so that information and experience of its practical application may be obtained. Comments arising from the use of this Draft for Development are requested so
4、 that UK experience can be reported to the European organization responsible for its conversion into a European Standard. A review of this publication will be initiated 2years after its publication by the European organization so that a decision can be taken on its status at the end of its three-yea
5、r life. The commencement of the review period will be notified by an announcement in Update Standards. According to the replies received by the end of the review period, the responsible BSI Committee will decide whether to support the conversion into a European Standard, to extend the life of the pr
6、estandard or to withdraw it. Comments should be sent in writing to the Secretary of BSI Technical Committee EPL/97, Lighting and beaconing of aerodromes, at 389Chiswick High Road, LondonW44AL, giving the document reference and clause number and proposing, where possible, an appropriate revision of t
7、he text. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement international or European publication
8、s referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. Summary of pages This document comprises a front cover, an inside front cov
9、er, pagesi andii, theENV title page, pages2to12 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsDDENV5023
10、2:1997 BSI 03-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of ENV 50232 3ii blankEUROPEAN PRESTANDARD PRNORME EUROPENNE EUROPISCHE VORNORM ENV 50232 February 1997 ICS 93.120 Descriptors: Electrical installation, lighting, arodrome, transformer, specification, designation
11、, classification, test, marking English version Aeronautical ground lighting electrical installation Isolating transformer: Equipment specifications and tests This European Prestandard (ENV) was approved by CENELEC on 1996-07-02 as a prospective standard for provisional application. The period of va
12、lidity of this ENV is limited initially to three years. After two years the members of CENELEC will be requested to submit their comments, particularly on the question whether the ENV can be converted into a European Standard (EN). CENELEC members are required to announce the existence of this ENV i
13、n the same way as for an EN and to make the ENV available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the ENV) until the final decision about the possible conversion of the ENV into an EN is reached. CENELEC mem
14、bers are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit E
15、uropen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1997 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. ENV 50232:1997 EENV50232:1997 BSI 0
16、3-1999 2 Foreword This European Prestandard was prepared by the CENELEC BTTF72-3, Lighting fittings for aerodromes. The text of the draft was submitted to the CENELEC questionnaire and vote and was approved as ENV50232 on1996-07-02. The following date was fixed: Contents Page Foreword 2 Introduction
17、 3 1 Scope 3 2 Normative references 3 3 Definitions, symbols and abbreviations 3 3.1 Definitions 3 3.2 Symbols and abbreviations 4 4 General requirements 4 4.1 Isolating transformer 4 4.2 Connection cables 4 4.3 Electrical characteristics 5 5 Type and production tests 6 5.1 Type tests 6 5.2 Requalif
18、ication tests 6 5.3 Production tests 6 6 Tests description 6 6.1 On load current ratio 6 6.2 Power factor 7 6.3 Efficiency 8 6.4 Short circuit current 8 6.5 Off load voltage 8 6.6 Dielectric strength 8 6.7 Current leakage 8 6.8 Fall test 10 6.9 Pull test 10 6.10 Soaking tests 10 6.11 Dimensional tes
19、ts 10 6.12 Ageing test 10 6.13 Cycling test 11 6.14 Temperature rise test 11 6.15 Surge test 12 Page 6.16 Gas tightness test 12 7 Classification and designation 12 7.1 Classification 12 7.2 Marking, labelling, packaging 12 Figure 1 Intensities boundaries for isolating transformer 5 Figure 2 transfor
20、mer under test 7 Figure 3 7 Figure 4 9 Figure 5 9 Figure 6 Example of set up for primary leakage test 9 Figure 6 12 Table 1 4 Table 2 Limits of current measured on A4 10 Table 3 10 Table 4 10 Table 5 12 latest date by which the existence of the ENV has to be announced at national level (doa) 1996-12
21、-01ENV50232:1997 BSI 03-1999 3 Introduction This prestandard concerns isolating transformers used in electrical series circuits for supplying ground airport lighting luminaires, installed to give pilots visual cues during approach, landing, take off and taxiing. These lights are not used to light an
22、y ground surface, but shall provide some references to pilots. This is why there is a strong link between the following requirements and those issued from ICAO standards. 1 Scope This prestandard specifies the nominal characteristics of the isolating transformers used in airfield ground lighting for
23、 6,6A series circuits supplied by Constant Current Regulators up to30kW in rating. This prestandard is applicable to isolating transformer used to supply through its secondary circuit airport lighting luminaires. The isolating transformer provides electrical insulation, between the primary circuit s
24、upplied by a constant current regulator and the secondary connected to the load (generally the lamp of the luminaire) under conditions specified in this prestandard. Specific transformers used to deliver a alternative voltage or a constant current on its secondary circuit, are not included in this p
25、restandard. The document is in accordance with ICAO Annex14. In any case any new operational need for Air Navigation Safety could change some data or principle issued in this document. 2 Normative references This European prestandard incorporates by dated or undated reference, provisions from other
26、publications. These normative references are cited at appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revisi
27、on. For undated references the latest edition of the publication referred to applies. ENV 50231, Aviation ground lighting electrical installation Constant current regulator: Equipment specifications and tests. prENV 50233, Aviation ground lighting electrical installation Connecting devices: Equipmen
28、t specifications and tests. EN 60742, Isolating transformer and safety isolating transformers Requirements (IEC742+A1,mod.). HD 383, Conductors of insulated cables (IEC228). ICAO, International standards and recommended practices, Aerodromes Annex14 to the Convention on International Civil Aviation,
29、 Volume1 and2, Aerodrome Design and Operations (Issued by International Civil Aviation Organisation). ISO 9002, Quality systems Model for quality assurance in design, development, production, installation and servicing. 3 Definitions, symbols and abbreviations 3.1 Definitions For the purposes of thi
30、s prestandard the following definitions apply, as well as those given in ICAOAnnex14. 3.1.1 isolating in all this document the word “isolating” shall be interpreted as defined in EN60742 3.1.2 type test a test for the purpose of checking compliance of the design of a given product with the requireme
31、nts of the relevant specification. Type tests are selected in agreement with the manufacturer or responsible vendor 3.1.3 production test a test for the purpose of checking the compliance of a batch of series products for acceptance. This test is defined in this standard 3.1.4 rated voltage the RMS
32、voltage at which the transformer was designed to operate under normal load conditions 3.1.5 nominal wattage the wattage at which the transformer was designed to supply full resistive load under normal conditions 3.1.6 rated current the RMS current at which the transformer was designed to operate 3.1
33、.7 rated frequency the frequency or frequency range for which the transformer has been designedENV50232:1997 4 BSI 03-1999 3.1.8 isolating transformer isolating transformers are defined in EN60742 3.1.9 safety isolating transformer safety isolating transformers are defined in EN60742 3.1.10 safety E
34、xtra-Low Voltage (SELV) safety Extra low voltage is defined in EN60742 3.2 Symbols and abbreviations 4 General requirements 4.1 Isolating transformer The rated primary current shall be 6,6A. The transformers shall be enclosed in a permanently sealed insulating case so as to produce a completely wate
35、rtight assembly. The thickness of the encapsulation shall be not less than 6,5mm anywhere, whatever the type of encapsulation. The transformers shall have two electrically and physically separate windings, one primary and one secondary wound on a magnetic circuit. The magnetic core shall have no con
36、nection neither to earth, nor to one of the electrical circuits. An external earthing terminal linked to a well identified pole of the secondary may be required. All internal connections shall be made by high-pressure crimping or high-temperature soldering. The nominal characteristics as the nominal
37、 values on the secondary and the nominal wattage are specified inTable 1. Table 1 The encapsulation of the transformers shall provide a continuous and watertight bond with its connection cables/connectors. The construction of the transformer shall ensure its characteristics given in4.3 and the diele
38、ctric strength between the primary circuit on one hand and either the secondary circuit or the outside surrounding on the other hand shall be at least12kV RMS for1min. The minimum length of the creepage path between primary and secondary shall be as specified in EN60742. 4.2 Connection cables 4.2.1
39、Primary cables The isolating transformer shall be connected to the airfield lighting primary series circuit cable via two flexible copper cables with at least 6mm 2cross section, and minimum length 50cm. The rated service voltage for the cable shall be 6kV test voltage 35 kVDC. One cable shall have
40、a moulded on male prENV50233type1, class A, style2 connector at its end. The other cable shall have a moulded on female prENV50233type1, class A, style9 connector. 4.2.2 Secondary Connection shall be by a section of two-pole cable of section 2 4mm 2or 2 2,5mm 2 , service voltage minimum 600V and min
41、imum length of 1,2m. These cables shall have female prENV50233 type2, class A, style7 or8 connectors at their ends. IT: Isolating transformer used in airfield lighting. CCR: Constant Current Regulator as specified in ENV50231. A1, A2: primary and secondary currents measured by ammeters. V1, V2: prim
42、ary and secondary voltages measured by voltmeters. W1, W2: wattage measurements of respectively primary and secondary circuit of IT. Nominal wattage W Primary current A 45 6,6 65 6,6 100 6,6 150 6,6 200 6,6 300 6,6ENV50232:1997 BSI 03-1999 5 4.2.3 Characteristics The connectors shall be protected by
43、 watertight plugs/caps. The connector encapsulation, the cables sheath and the transformer body shall be made of compatible materials. No cracks shall appear at the junctions between them, when the transformer and its connectors is manufactured as a single entity. The primary and secondary cables sh
44、all be flexible, class5 or6 specified in HD383. 4.3 Electrical characteristics 4.3.1 Secondary current The tolerance on the secondary current for nominal loading and a rated current shall be equal to the nominal value 1 %, i.e. 6,53A or 6,67A. 4.3.2 Power factor At nominal resistive load and rated p
45、rimary current, for all types of transformer, the power factor shall be greater than95%. 4.3.3 Efficiency At nominal resistive load and rated primary current the efficiency of the transformer shall be atleast85% for transformers rated below and equal to70W and 90 % for transformers rated above70W. 4
46、.3.4 Short-circuited secondary For a rated primary current, the secondary short-circuit current shall be less than 6,90A. 4.3.5 Off-load voltage With the secondary in open circuit, the r.m.s. voltage at its terminals shall not exceed 50V for all type of transformers. 4.3.6 Acceptable load In order t
47、o take account of the lamp power tolerances, losses in the cables connecting the lights to the transformers, and tolerances on the primary current, the permanent allowable load on the secondary could be above the nominal value in a such a way that the secondary intensity shall be maintained inside o
48、f the limits described in4.3.7 when the load is increased to 120% of the nominal value. NOTEFor a secondary current I, different from 6,6A, the corresponding correcting factor (I/6,6A) shall be applied to the present values. Figure 1 Intensities boundaries for isolating transformerENV50232:1997 6 BS
49、I 03-1999 4.3.7 Intensity diagram In any case, for any load from 0% to 120% of the rated value the secondary current shall be maintained inside of the boundaries described inFigure 1. 4.3.8 Overheating Over heating shall be determined using the resistance method and shall be less than 55K, with the transformer operating in air at an ambient temperature of 20C 2C, with rated current flowing in the primary, in all the following conditions: nominal resistive load; short circuit; open circuit. 5 Type and production tests 5.1 Type tests The pur
