BS EN 15625:2009 pdf download
BS EN 15625:2009 pdf download.Railw ay applications一 Braking- Automatic variable load sensing devices.
It shall be demonstrated that these environmental conddions have been taken into account in the design of the automatic vanable 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 specificaly 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 lollowing environmental conditions on the automatic variable load sensing device, shalt be used In the developmenvdesign 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
200Cm.
4.4.3.3 HumidIty
The following external humidity levels shall be considered:
— yearly average: S 75 % relative humicty:
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/m3 occurring in tunnels.
An operationaly 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 as considered will not be exceeded for more than 30 days per yeat
At cooled surfaces, 100 % relative humidity can occur, causing condensation on parts of equipment: this shall riot lead to any malfunction or failure.
Sudden changes of the air temperature local to the vehicle can cause condensation of water on parts of equipment with rate of 3 K/s and maximum variation of 40 K; these conditions particularly occurring when entering or leaving a tunnel shall not lead to any malfunction or failure of the equipment,
4.4.3.4 Raing
Ram rate shall be taken into account. The effect of rain shall be considered depending on the possible equipment installation together with wind and vehicle movement.
Consideration shaM be given to the effect of all kinds of snow, ice and/or hail. The maximum diameter of hailstones shall be taken as 15 mm. larger diameter can occur exceptionally.
The effect of snow, ice and hail shall be considered depending on the equipment installation together with wind and vehicle movement.
4.4.3.6 SoLar radiation
Equipment design shall allow for direct exposure to solar radiation at the rate of 1120W/rn2 for a maximum duration of 8 h.
4.5 Compressed air quality
It shall be possible to operate the automatic variable load sensing device without restrictions with at least the compressed air quality according to the following classes defined by ISO 857312OO1:
— dass 4— for the maximum patide size and the maximum concentration of solid contaminants;
— dass 4 — for the water dew point;
— dass 4—for the maximum total (droplets, aerosols and vapours) oil concentration,
The automatic variable load sensing device shall be capable of operating In an air supply system that Is not titled with an air dryer, or when the air dryer Is out of order. The air system should therefore wtclude some means of preventing water collecting within the automatic vanabie load sensing device and hence freezing of the water In conditions below 0 C.
4.6 Service life
No specific requirements for the automatic variable load sensing device to attain a particular service life are contained in this European Standard
Any testing to establish the service life of an automatic variable load sensing device shall be conducted as part of the product development.
NOTE The service life of the automatic variable load sensing device is a function of the environment/operating conditions m which the automatic vanabte load sensing device iaN function, and the requirements for the automatic variable load sensing device to achieve a serviceable lite In accordance with the maintenance requirements of the vehicle to ch it is fitted.
