1、AECMA PREN*K2350 89 LOL23LL 0007854 2 i-; prEN 2360 A.E.C.M.A. STANDARD Edition 1 NORME A.E.C.M.A. A.E.C.M.A. NORM January 19EB - EDITE PAR LASSOCIATION EUROPEENNE DES CONSTRUCTEURS DE MASRIEL AEROSPATIAL 88. boulevard Malerherber. 76008 PARIS -TEL 46.63-82-86 UDC : 621.31 6.67 : 629.7 Key words : A
2、ircraft industry, aircraft equipment, circuit breaker, msnufecturlng requirement, specification, test, testing condition, environment, marking. ENOLISH VERSION Aerospacb series Circuit bmaken Technical 8p;ecification Srie e6rospatlale Disjoncteurs Spcification technique Luft- und Raumfahrt Schutzsch
3、alter technlrche Lleferbedlngungen . Ths .Aerospace series. standardhas been drawn up under the rasponribility of AECMA (Association Europenne des Constructeurs de Matriel Arospetiall. It it published on yellow paper n three equivalent versions (English. French, Gernfan). It will be submined as a dr
4、af European Standard to CEN (European Committee for Standardization) for final voie. .- The equivalent version8 in Frencb German languigo8 can e MfrO.V8lh1rf It - FRANCE /il nwmn la- AECMA PREN82350 89 I 10L23LL 0007855 4 0 prEN 2350 Page 2 CONTENTS 1 Scope and fleld of appllcatlon 2 References 3 De
5、f In1 tlons 4 Deslgn 5 Tests - Recplrements - Procedures -I Evaluation 6 Qual If Icatlon 7 Perlodlc tests to malntain quallflcation 8 Acceptance 9 Marking AECMA PREN*Z350 89 E 1012311 0007856 b T 1 Scope and field of application prEN 2350 Page 3 This standard gives design information and specifies t
6、est methods for aircraft circuit breakers covered by EN standards. It is applicable if it is referred to in these standards. 2 References IS0 2669 IS0 2859-1974 IS0 7137 IEC Publication 50 EN 2000 MIL-A-8243D MIL-H-5606E MIL-L-23699C M I L-C- 2 5769 J MI L- L-78085 MIL-L-7870A MIL-G-5572F MI L-H-832
7、82C SAE AS 1241 3 Definitions - Environmental tests for aircraft equipment - Part 3.2 : Steady state acceleration Sampling procedures and tables for inspection by attributes Aircraft - Environmental conditions and test procedures for airborne equipment International electrotechnical vocabulary Chapt
8、er 441 : Switchgear, controlgear and fuses Aerospace series - Quality assurance requirements for the manufacture and procurement of EN aerospace standard products Anti-icing and deicing - Defrosting fluid Hydraulic fluid, petroleum base, aircraft, missile, and ordnance Lubricating oil, aircraft turb
9、ine engine, synthetic base Cleaning compound, aircraft surface, alkaline waterbase Lubricating oil, aircraft turbine engine, synthetic base Lubricating oil, general purpose, low temperature Gasol i ne avi at i on grades 80/87 , 100/30, 115/145 Hydraulic fluid, fire resistant, synthetic hydrocarbon b
10、ase, aircraft, metric - Fire resistant phosphate ester, hydraulic fluid for aircraft - Circuit breaker with “trip-free release“ : A circuit breaker in which the “open“ command takes precedence over the “close“ command, i.e when the electrical trip condition is reached and pressure is exerted on the
11、depressed actuator button, the circuit is sti 11 automatically opened. - Poles of a circuit breaker A circuit breaker pole denotes any main circuit from the input to the pertinent output termi na1 . AECMA PREN*Z350 89 LOL231L 0007857 8 S prEN 2350 Page 4 The parts of each current path (contacts, sen
12、sors, switching parts) are independent and electrically isolated. There may be 1, 2 or 3 poles independently of any auxiliary circuits. - Current rating (In) : The current rating (In) of a circuit breaker is the current in amperes for which the circuit breaker has been designed and designated. Trip
13、characteristics and test values are based on the current rating. - Voltage ratings : Voltage ratings are the voltage levels in volts for which the circuit breaker is designed. Insulation values and test voltages are related to these rated voltages. - Indication of current and voltage values Unless o
14、therwise. specified, the a.c. voltage and a.c. current values shown are r.m.s. values. For other definitions, see IEC Publication 50 - Chapter 441. 4 Design 4.1 Insulating housing In addition to the switching mechanism, the insulating housing shall incorporate the connecting and mounting systems. 4.
15、2 Trip-free mechanism The circuit breaker shall be designed to permit trip-free release, i.e. so that it is switched off at overload and remains switched off even when the button is held in the closed position. Resetting of the circuit breaker shall be possible only after complete release of the act
16、uator button. In no case shall operation under these conditions affect the further serviceability of the circuit breaker. All poles of a multi-pole circuit breaker shall trip on single or multi-phase overload. The time lag between opening of the first and last pole shall not exceed 10 ms. 4.3 Mounti
17、ng All visible parts shall be black and non-reflective. 4.4 Electrical connection components These shall be suitable to fit the cable lugs (or contacts). I AECMA PREN*2350 89 1012311 0007858 T I prEN 2350 page 5 4.5 Actuator button In the closed position the visible part of the actuator button shall
18、 be black. In the “off“ (open) position a white strip shall be exposed. The outer part of this button shall be insulated from all live parts. In no case shall the actuator button remain in an intermediate position or give an incorrect indication of the switching condition of the circuit breaker. It
19、shall not be removable. - The circuit breaker contacts shall be closed by pushing the actuator button. - The circuit breaker contacts shall be opened by pulling the actuator button. The current rating of the circuit breaker shall be indicated indelibly in white on the top of the actuator button. Arr
20、angement of the digits is indicated in the product standard. 4.6 Calibration safety device The circuit breaker shall be designed in such a way that the calibration cannot be interfered with without breaking a seal. 4.7 Leakage paths Leakage paths and the minimum distance to be observed between live
21、parts and all other parts of the circuit breaker in non-insulating materials and between live parts of opposite polarity shall be sufficient to avoid damage and spark- over under all operating and ambient conditions. 4.8 Insulants Insulating parts shall be of non-inflammable or self-extinguishing ma
22、terials and shall not emit noxious or explosive vapours. They shall be resistant to fungus growth and the effects of micro-organisms. Protective coatings and materials which may chip, crack or shatter shall not be used. 4.9 Protection against corrosion All metal parts shall be either resistant to or
23、 protected against corrosion, In case of contact between dissimilar metals they shall be protected against electrochemical corrosion. Where bimetals are used, any corrosion which may occur shall not affect the proper function of the circuit breaker. AECMA PREN*Z350 89 E 1012311 0007859 II E prEN 235
24、0 Page 6 4.10 Fasteners Screws and nuts shall be so locked that the connections cannot be damaged. 5 Tests - Requirements 5.1 General 5.1.1 Un1 ess ot herwi se Ambient temperature 23 - Procedures - Evaluation indicated, measurement conditions are as fol lows : t 5“ c _ . - -_ - _- -* _ Pressure 840
25、to 1 070 hPa (1) Relative humidity 5 85 % 5.1.2 Mechanical tests shall be carried out with the circuit breakers mounted in their normal position on a metal holder at least 2 mm thick. 5.1.3 For thermal tests the circuit breakers shall be mounted with the minimum distance between each other as specif
26、ied in the product standard. 5.1.4 For electrical tests the circuit breakers shall be connected to cables as shown in table 1. The cables shall be at least 0,5 m long. Where several circuit breakers or the poles of multi-pole circuit breakers are connected in series, the connecting cable between the
27、 circuit breakers or poles shall be 2 x 0,5 m long. The cable lugs used shall be compatible with the circuit breaker terminals. Table 1 Current rating A up to 1 1,5 to 6 7 to 10 11 to 15 16 to 20 21 to 25 26 to 40 41 to 50 Cross section mm2 3 5 9 14 Corresponding AWG *) Cross section - 20 18 16 14 1
28、2 10 8 6 *) American Wire Gauge 1) 1 hPA = 1 mbar AECMA PRENm2350 89 1012311 0007860 8.1 y prEN 2350 Page 7 5.2 Mechani cal tests 5.2.1 Visual inspection It shall be performed without magnification. It concerns : - General appearance (surf ace fi ni sh, colour, assembly) - Conformity and quality of
29、markings and inscriptions - Undamaged condition of calibration seal - After climatic environmental tests, inspection of all parts which may show corrosion or poor legibility or markings. 5.2.2 Dimensions and masses These shall conform to the requirements of the product standard and shall be checked
30、using normal measuring instruments. 5.2.3 Actuating components 5.2.3.1 Actuator button travel With the circuit breaker in the closed and open positions the dimension of the end of the actuating button in relation to the mounting surface is measured, parallel to its longitudinal axis (direction of tr
31、avel). This measurement is performed three times, with one mechanical switching operation between each measurement. The mean values of the measurements recorded shall lie within the tolerances specified in the product standard. 5.2.3.2 Operating force The force required to switch “on“ and itoff“ sha
32、ll be measured with a suitable gauge in the line of travel of the actuator button. The measurement shall be taken three times in each direction. The mean value of the measurements shall lie within the limits indicated in the product standard. 5.2.3.3 Strength of actuating components - Transverse loa
33、d The push button in the closed and open position shall be subjected to the load specified in the product standard at the end (rim) of the button, perpendicularly to the direction of travel. The load shall be applied for 1 minute each in the four main directions. - Longitudinal load The push button
34、shall be subjected to the force specified -in the product standard, for 1 minute each in the push and pull directions. No damage shall be caused by the loads applied. Evaluation : Verification tests A + E + F + C in table 4. AECMA PREN*Z350 89 I LOL23LL 08078bE T m prEN 2350 Page 8 5.2.4 Strength of
35、 mounting - Mounting The tightening torque specified in the product standard shall be applied 3 times for 1 minute each, with one disassembly included. - Rotation The circuit breaker housing shall be turned around its mounting in both directions successively at the torque specified in the product st
36、andard. No deformation outside tolerances or rupture of the locating device shall result. The circuit breaker housing shall not break. - Evaluation Verification tests : A + E + F + C in table 4. 5.2.5 Strength of connections - Tightening torque The connection screws shall be tightened to the torque
37、specified in the product standard. This torque shall be maintained for 1 minute. The connection screws shall then be loosened. This test shall be carried out five times. No deterioration of the connections shall result. There shall be no breakage of the circuit breaker housing. - Strength of connect
38、ions Each of the contact lugs (or terminals) shall be subjected to the forces indicated in the product standard. The-forces shall be maintained for 1 minute and shall not lead to deterioration of the connections. The circuit breaker housing shall not break. - Evaluation - - - _-.- _ - - - - - Verifi
39、cation tests A + C in table 4. AECMA PRENx2350 89 L0123Ll 0007862 L I: 5.3 Environmental tests 5.3.1 Vi brat i on perf ormance - Mounting shall be designed so as to transmit the vibrations over the wh range without absorption or natural resonance. The electrical connection shall be made with cables
40、of the se in table 1. The connection cables shall be attached approx. termi na1 s. - Procedure The circuit breakers shall be subjected to the sinusoidal wave test to IS0 7137. The test shall be carried out in 3 mounting positions along the circuit breaker, at ambient temperature, in the closed and T
41、he values shall conform to the limits specified in the product - Total vibration time per direction : in the closed position : 2 hours, circuit breaker load 90 % 1, in the open position : 1 hour. determined as follows : - resonance : if applicable - 30 min per resonance - sweep During the test it sh
42、all be established that the contacts do period equal to or greater than 10 ps (circuit breaker in the O open for a period equal to or greater than 10 ps (circuit-break position). - Evaluation Verification tests A + D + G + C to table 4. 5.3.2 Mechanical shocks - Mounting m I : remainder of total tim
43、e specified. e vibration. the terminals. I AECMA PRENm2350 89 I LOL231iL 0007863 3 I prEN 2350 Page 10 - Procedure The circuit breakers shall be subjected to the mechanical shock test to IS0 7137. 3 shocks shall be applied in each direction and for each switch setting (at ambient temperature) : - in
44、 the closed position at 90 % of current rating - in the open position. The acceleration peak value (half sine-wave form of 11 ms duration) is specified in the product standard. During the test it shall be established that the contacts do not close for a period equal to or greater than 10 ps (circuit
45、 breaker in the open position) or open for a period equal to or greater than 10 ps (circuit breaker in the closed posit i on). - Evaluation Verification of dimensions Verification tests A + C to table 4. 5.3.3 Centrifugal acceleration - Mounting The circuit breakers shall be mounted on the centrifug
46、e, by.means of a movable support. The connection cables shall be attached to the support approximately 100 mm from the terminals. The circuit breakers shall be shielded from air flow by a screen. - Procedure The behaviour of the circuit breakers in steady-state acceleration shall be tested to IS0 26
47、69. The test shall be carried out for 6 planes of the main axis of the circuit breaker. Two tests are required per circuit breaker in each direction (at ambient temperature) : - 1st test : 10 min in the open position - 2nd test : 10 min in the closed position, at 90 % of current rating. The accelera
48、tion value is specified in the product standard. During the tests it shall be established that the contacts do not close for a period equal to or greater than 10 ps (circuit breaker in the open position) or open for a period equal to or greater than 10 ps (circuit. breaker in the closed position, at
49、 90 % i,). - Evaluation Verification tests A + C to table 4. AECMA PREN*2350 89 1012311 0007864 5 I D _- . -. 5.4 Climatic environmental tests 5.4.1 Sand and dust - Mounting The circuit breakers shall be mounted on a support in the test chamber so that they are completely exposed to the air flow. The circuit breakers (no current) shall be in the closed positio cycle and in the open position for the second. - Procedure The circuit breakers shall be subjected to the sand and dust tes The test shall be carried out exposing all 6 surfaces of the ci the sand stream, e
