BS EN 15625:2009 pdf download – Railway applications — Braking — Automatic variable load sensing devices

BS EN 15625:2009 pdf download – Railway applications — Braking — Automatic variable load sensing devices
The automatic variable load sensing device shall fulfil the specified requirements during a random vibration test in accordance with EN 61373:1999, Clause 8. The automatic variable load sensing device shall withstand a simulated long life test at increased random vibration levels in accordance with EN 61373:1999, Clause 9, without any loss of performance.
The automatic variable load sensing device shall withstand shock testing in accordance with EN 61373:1999, Clause 10, without any loss of performance. The above shall be tested in accordance with 6.2.8.
4.4 Environment
4.4.1 General The design shall take into account that the automatic variable load sensing device shall be able to be put into service and operate normally in the conditions and climatic zones for which it is designed and in which it is likely to run, as specified in this European Standard.
NOTE 1 The environmental conditions are expressed in classes for temperature etc. thereby giving the vehicle designer the choice of an automatic variable load sensing device suitable for operation on a vehicle all over Europe, or have a restricted use. NOTE 2 The environment range limits specified are those that have a low probability of being exceeded. All specified values are maximum or limit values. These values may be reached, but do not occur permanently. Depending on the situation there can be different frequencies of occurrence related to a certain period of time. NOTE 3 The environment requirements of this European Standard cover the environment requirements of the HS RST TSI which only refers to EN 50125-1:1999. The automatic variable load sensing device shall be tested in accordance with requirements given in Clause 6 including where required environmental/climatic testing.
4.4.2 Temperature The automatic variable load sensing device covered by this European Standard shall be able to operate:
at – 25 °C ≤ environmental temperature ≤ 70 °C without any deviation from the technical requirements specified in Clause 4;
at – 40 °C ≤ environmental temperature < – 25 °C with allowed deviation from the technical requirements specified in this European Standard but without affecting the function of the automatic variable load sensing device. Deviations from the technical requirement when testing at extremes are defined in 6.2.7. The purchaser can specify higher or lower extreme temperature limit values if operational constraints demand it. In this case the temperature limit values used in the extreme temperature tests of 6.2.7 shall be changed accordingly. 4.4.3 Other environmental conditions 4.4.3.1 General The following environmental conditions shall be considered in the design of the automatic variable load sensing device. It shall be demonstrated that these environmental conditions have been taken into account in the design of the automatic variable load sensing device. It is sufficient for the supplier to make a declaration of conformity stating how the environmental conditions in the following clauses have been taken into account. If not specifically required to be tested as part of the type testing requirements in Clause 6, suitable tests and/or design assessments considering the effect of the following environmental conditions on the automatic variable load sensing device, shall be used in the development/design proving of the automatic variable load sensing device, prior to type testing. 4.4.3.2 Altitude The automatic variable load sensing device shall be able to operate without restrictions up to an altitude of 2 000 m. 4.4.3.3 Humidity The following external humidity levels shall be considered: yearly average: ≤ 75 % relative humidity; on 30 days in the year continuously: between 75 % and 95 % relative humidity; on the other days occasionally: between 95 % and 100 % relative humidity; maximum absolute humidity: 30 g/m 3 occurring in tunnels. An operationally caused infrequent and slight moisture condensation shall not lead to any malfunction or failure. The psychometric charts contained in EN 50125-1 shall be used to establish the range of variation of the relative humidity for the different temperature classes that it is considered will not be exceeded for more than 30 days per year. At cooled surfaces, 100 % relative humidity can occur, causing condensation on parts of equipment; this shall not lead to any malfunction or failure.