1、bsolescentl B G. 200: August, 1967 UDC 629.13.066 : 621.316.542.1-514.4 BRITISH STANDARDS INSTITUTION INcoRpoRATED By mm Tekphone: 01-629 9ooo Tekmana: STANDARDS LONDON W1 BRITISH STANDARDS HOUSE, 2 PARK STREEi“, LONDON, W.1 BRITISH STANDARD : AEROSPACE SERIES SPECIFICATION FOR MINIATURE LEVER-OPERA
2、TED MANUAL SWITCHES FOREWORD This British Standard has been prepared as a result of enquiries within the aircraft industry which showed a need for a switch of smaller size and rating than those in British Standard G.194 yet larger than the miniature switches complying with the American specScation M
3、IGS-8834. The specScaton has been based on British Standard G.194, Lever-operated manual switches for aircraft, and, in addition to specifying performance requirements, denes preferred dimensions and Mg holes. Switches are classified according to the environmental conditions for which they are suita
4、ble. The tests, which are grouped as type tests, production tests and quality tests, include a test of the force required to operate the switch, and recommendations as to suitable tests for verifying the serviceability of the switches after storage or use. This standard makes reference to the foiowi
5、ng British Standards: British Standard 2G.100. General requirements for electrical equipment and indicating instruments for aircraft. British Standard G.177. Nyvin type electrical cables for aircraft. British Standard G.178. Crimped joints for general purpose electrical cables for aircraft. British
6、Standard SP.20. Panel type au filter elements for use with internal combustion engines and compressors on aircraft. BS 410. Test sieves. BS 580. Trichloroethylene. NOTE. Where metric equivalents are given, the figures in British units ara to be regarded as the standard. The metric equivalents are ap
7、proximate. More amate conversions should be based on the tables in BS 350, Conversion factors and tables. Obsolescent (by Amendment No. lh The need for the equipment covered by this British Standard has been reviewed and it has been decided that, in the interests of rationalization, it should be 1 :
8、regarded as obsolescent and not therefore used for new designs. The standard I will be withdrawn in due course. fi - I BSI G*ZOO 67 W Lb24669 OLOBb90 1 W G. 200 t August, 1967 CONTENTS 1. GENERGLREQUIREMENTS 1.1 scope 1.2 General 1.3 Rating 1.4 Declarations . 1.5 Marking 2. PARTICULAR REQUIREME“ 2.1
9、 Operation . 2.2 Construction . 2.3 Dimensions . 2.4 Environmental requirements . 3. TESTS 3.1 General TYPETESTS 3.2 Mechanical strength tests , 3.3 Operating force test 3.4 Mechanical endurance tests . 3.5 Voltage drop test 3.6 Nigh voltage and insulation tests 3.7 Temperature rise test 3.8 Electri
10、cal endurance tests . 3.9 Overload tests . 3.10 Short-circuit tests 3.11 Vibration test . 3.12 Acceleration test 3.13 Climatic test . 3.14 Lever bush sealing test. . 3.15 Switch sealingtest 3.16 Explosion-proofness . . . . . . . . . u . . . , * . e e. . . e . . . . . . . . . . . . . . . e . . 2 2 2
11、3 3 3 3 3 3 4 4 4 4 5 5 5 5 5 5 5 6 6 6 6 6 3.17 Salt corrosion test 3.18 Dust and sand test 3.19 Fluid contamination tests . 3.20 Strip examination and report . 3.21 Marking and operation . 3.22 Operating force test PRODUCTION TESTS 3.23 Voltage drop test 3.24 High voltage and insulation tests QUAL
12、ITY TESTS 3.25 Selection of samples 3.26 Electrical endurance test . 3.27 Vibration test . 3.28 Lever bush sealing test 3.29 Switch sealing test 3.30 Strip examination and report . APPENDICES A. Type test schedule B. Serviceability tests C. Salt corrosion test D. Dust and sand test E. Fluid contamin
13、ation tests . FIGURES 1. Envelope dimensions for miniature lever-oDerated manual switches 2. 3. Typical test circuit for short-circuit test . 4. Measuring device for dust and sand test . Fixingholes and details of locating washer . SPECIFICATION 1. GENERAL REQUIREMENTS 1.1 SCOPE This British Standar
14、d specifies the requirements for two classes of singlehole fixing, miniature lever-operated manual switches for use in nominal 28 Vd.c. and 115/200 V three-phase, 400 cycle a.c. system in aircraft. Class 1 switches are sealed and are suitable for higher altitude and wider temperature conditions than
15、 Class 2, which are sealed only at the lever entry. 1.2 GENERAL 13.1 The switch shall comply with the requirements of this British Standard, those of British Standard 2 G. 100 and those of the relevant switch drawings. 1.2.2 The switch shall be suitable for either of the following temperature and al
16、titude classifications : Class 1. Suitable for use at altitudes up to 70000 ft (21 400 m) and for temperatures within the range -40C to f70“C; they should not suffer damage or deterio- ration when subjected to -65C. Class 2. Suitable for use at altitudes up to 20000 ft (6100 m) and for occasional us
17、e at 60 o00 ft (18 300 m), and for temperatures within the range -20C to I-55C; they should not suffer damage or deterioration when subjected to -40C. . . . a . . . . . . . t . . *I. . . . . . . . . a . . .*. . e . . . . It. . . . . r. .*. 6 6 6 6 7 7 7 7 7 7 7 7 7 7 8 9 9 9 9 10 11 11 12 1.2.3 The
18、switch shall be suitable for mounting through the panel from the rear and shall operate satisfactorily when mounted in any attitude, 1.2.4 The switch may be the two- or three-position type, with one or more poles: it may be self-retaining and/or spring return. It should preferably be designed to all
19、ow the incorporation of integral locking of the lever in any or ali positions. 1.2.5 The method of operation of the switch shall be by means of a single lever, moving in a plane at right angles to the mounting panel. The relationship of the lever positions to the keyway shall be as shown in Fig. 1,
20、and the relationship of the terminal numbers to the lever posi- tions shall be as stated in the individual specification*. 1.2.6 The switch terminals shall be identified by number in the sequence shown in the individual specification*. 1.3 RATING 1.3.1 Voltage. The switch shall operate in nominal 28
21、 V d.c. and 115/200 V three-phase, 400 cycle a.c. systems having the characteristics specified in British Standard 2 G. 100: Part 3. In addition, the switch shall be suitable for use at voltages down to 4 V d.c. or a.c. *Attention is drawn to the fact that it has not been found practicable to standa
22、rdize these features. 2 G. 200 : August, 1967 1.3.2 Current. The switches shall be suitable for all of the following normal current ratings: (1) 5 A resistive load (2) 3 A inductive load (3) 2.5 A tungsten Glament lamp load (28 V d.c.) (4) 1-5 A tungsten filament lamp load (200 V a.c.) In addition,
23、unies otherwise declared, the switch shall be suitable for operation at 100 mA resistive load at voltages down to 4 V. The inductive loads shall be as follows: 28 V d.c.-3 A 40 mH 115/200 V a.c.-3 A 0-70 power factor lagging. In addition to the declarations required by British Standard 2 G. 100: Par
24、t 1, the manufacturer shall declare: 1.4 DECLARATIONS (i) The classification. (2) The limits of the forces necessary to operate the (3) The system of batchingusedfor quality test sampling. (4) The switch operation relative to the lever position switch to any position. and the terminal numbering, 1.5
25、 MARKING 1.5.1 In addition to the terminal numbering, the following minimum information shall be clearly and indelibly marked on each switch: (i) British Standard G. 200 and classifkition. (2) The manufacturers name or identification. (3) The manufacturers type number. (4) 5 A res. (Le. res. =resist
26、ive). (5) 28 V d.c./200 V a.c. 1.5.2 The application of some identifying mark to indicate the date of manufacture is recommended, 2. PAR“LARU3QUIREMENTS 2.1 OPERATION 2.1.1 The switch lever action shall be positive and it shall not be possible during normal usage for the lever to stay in any positio
27、n other than a fully-operated position. The operation of the switch shall not be affected adversely by the speed of movement of the lever. 2.1.2 It shall not be possible to rotate the lever about its longitudinal axis. 2.1.3 The anguiar movement of the lever should preferably be 20f2“ from the centr
28、al position, but angular move ments up to 23 &2“ are acceptable. 2.1.4 There shall be at least a 10“ movement of the lever before switching occurs. 2.1.5 The lever shall be capable of withsfanding without damage or distortion a force of 20 lbf (9 kgf) applied steadily in the directions specified in
29、3.2.2. 2.2 CONSTRTJCXION 2.2.1 The lever, including any metal inserts, shall be insulatedfrom all live parts. 2.2.2 The force required to operate the switch shall be not less than 1 lbf (0.45 kgf) and not more than 10 lbf (4.5 kgf). For each operation, of a particular type of switch, the maximurn fo
30、rce shall not exceed the minimum force by more than 100%. The manufacturer shall declare the maximum and minimum values of the force for each operation appropriate to each type of switch. 2.2.3 Where locking of the lever is provided, it shall be positive and automatic, and the lock shall be released
31、 by raising the lever against a spring force of 1.5 lbf to 5 lbf (0-7 kgf to 2.3 kgf). 2.2.4 The exposed portion of the switch shall have a non- glaring finish. 23.5 The switch shall be sealed at the point of entry of the lever to prevent the ingress of liquids or foreign matter. In addition, the bo
32、dies of Class 1 switches shall be sealed to the standard required by the test in 3.15. 2.2.6 Terminations shall be by screws, each capable of accepting two crimped tag-type terminations of approved design. The terminal threads shali be 4-40 UNC. Terminals shall have a mechanical strength adequate to
33、 satisfy the requirements of 3.2.1. 2.2.7 The terminal arrangement shall be such that wiring access is still provided when the switches are mounted in rows at minimum spacing. Means shall be provided to avoid accidental contact or short-circuiting between adjacent terminals. The switches shall be su
34、itable for close mounting and shall not constitute an electrical hazard if the side faces of adjacent switches touch one another. 23.8 The switch shall be mounted by means of a l%2-28UNS threaded bush with a locating keyway in the plane of movement of the lever. Two hexagon mounting nuts, one locati
35、ng washer and one internal shakeproof washer shall be provided with each switch. 2.2.9 The switch shall be so constructed that it is suitable for performing at least 50000 operations at maximum rated current and voltage. 2.2.10 The switch contacts, including common internal connections, should be se
36、lf-wiping on all switched contact positions. 2.2.11 The lever mechanism should incorporate a positive contact opening action in order to assist in breaking a tack weld. 2.2.12 The appropriate contacts only shall operate when the lever is suddeniy released from a spring-loaded position. 2.2.13 Spring
37、s should be of the compression type. 2.3 D-SIONS The envelope dimensions (including terminals) and the fixing arrangements for the switches shall be as shown in Fig. 1 and Fig. 2. 2.4 E“MENTA1L REQULREMENTS 2.4.1 The switch shall comply with the relevant require- ments of British Standard 2G.100:Par
38、t 2 in respect of mechanical and physical environmental conditions. Its grading for vibration, climatic and acceleration perform- ance shall be : Vibration: Grade B Acceleration: Grade Cy Class IA (i) and crash Grade E, class 11. Climatic: Class 1 or Class 2 as declared by the manufacturer. 2.4.2 cl
39、ass 1 switches shall also comply with the require- ments of 3.17, 3.18 and 3.19 of this British Standardin respect of resistance to salt corrosion, dust and sand, and fluid contamination. 2.4.3 Class 2 switches shall comply with the requirements of British Standard 2G.100: Part 2 for explosion-proof
40、 equipment. 3 G, 200 : August, 1967 3. TESTS 3.1 GENERAL 3.1.1 Nahue and order of tests. Tests shall be made to prove compliance with the relevant requirements of this British Standard, It is not intended or recommended that complete tests shall be made on every switch supplied. Three kinds of tests
41、, therefore, are specified as follows: (i) Type tests (3.2 to 3.20). Type tests shall be made on switches which have previously passed the production tests. For the purposes of this British Standard, switches of single-pole, double-pole and three-pole construction are considered as basic types. Each
42、 basic type of switch shall be subjected to type tests in accordance with the schedule in Appendix A. The environmental tests described in 3.17,3.18 and 3.19 need only be applied to one basic type of switch at the discretion of the Approving Authority. It is not intended that variants of a basic typ
43、e of switch shall be subjected to all of the tests: the extent of the type tests on such switches shall be agreed between the manufacturer and the Approving Authority.* Specified type tests may be required by the Approving Authority to be repeated after the introduction of a major modification. (2)
44、Production tests (3.21 to 3.24). Production tests shall be performed on every switch in the order stated. (3) Quality rests (3.26 to 3.29). Quality tests shall be performed on samples selected as specified in 3.25. Minimum tests recommended to verify the service- ability of switches after storage or
45、 use are indicated in Appendix B. 3.1.2 Test condions. All tests specified at a.c. voltages relate to 200 V (rine to he) for multi-pole switches, and to 115 V (phase) for single-pole switches. Ail electrical tests shall be performed with the switch connected on each side by Size 20 copper cored cabl
46、es complying with British Standard G.117. Except for the test in 3.10, each cable shall be 3612 in (914f50 mm) in length and shall be attached to the switch using a termin- ation of an approved design, crimped to the cable in accordance with the requirements of British Standard G.178. Unless otherwi
47、se specified, the tests shall be made at normal temperature (20f5“C) and pressure (700 mmHg to 800 mmI-Ig) and at a relative humidity not exceeding 90 %. 3.1.3 Cycle of operation. A cycle of operation shall consist of movement of the lever from one extreme position to the other and return to the ori
48、ginal position. Levers of witches of the spring-return type shall be allowed to return to the biased position without hindrance or assist- ance from the operating device. The times spent in each position shall be approximately equal. TYPE TESTS 3.2 MECHANICAL STRENGTH TESTS 3.2.1 Strength of termina
49、ls. All terminals shall be sub- jected for not less than one minute to : (1) A pull of 10 Ibf (4.5 kgf) in each of the following directions. (i) Parallel to the long axis of the terminal screw. - - *For switches for British civil or military aircraft the Approving Authorities are the Air Registration Board (through a design authority approved by the Board) and the Ministry of Technology respectively. (ii) At right angles to the long axis of the terminal screw. (2) A torque of 10 Ibf in (0.12 kgf m) applied to the terminal screw. 3.2.2 Strength of lever. A 20
