1 Scope
IEC/TR 62131‑3
, which is a technical report, reviews the available dynamic data relating to electrotechnical
equipment transported by rail vehicles. The intent is that from all the available
data an environmental description will be generated and compared to that set out in
IEC 60721.
For each of the sources identified the quality of the data is reviewed and checked
for self consistency. The process used to undertake this check of data quality and
that used to intrinsically categorize the various data sources is set out in IEC/TR 62131‑1.
This technical report primarily addresses data extracted from a number of different
sources for which reasonable confidence exist as to their quality and validity. The
assessment also presents data for which the quality and validity cannot realistically
be reviewed. These data are included to facilitate validation of information from
other sources. The report clearly indicates when it utilizes information in this latter
category.
This technical report addresses vibration and shock data from three different measurement
exercises, i.e. one on the UK rail system and two on the USA rail system. Although
one of these relates to a multimodal system in limited use world wide, data from it
are included to facilitate validation of information from other sources. The vast
majority of the rail measurements reviewed are from the USA and the remainder from
Western Europe. Some of the data sources considered indicate the inclusion of some
quite old vehicles. It has not been possible to identify the rail data considered
in setting the existing IEC 60721 severities.
Although the majority of the measurement exercises considered in this technical report
supplied both vibration and shock information, a number of measurement exercises are
biased towards the shock conditions of rail transportation. The severity and incidence
of shocks is mostly related to the occurrence shunting of individual wagons. The occurrence
of shunting of individual wagons is in turn dependant upon the operational strategy
adopted by the national rail systems. A significant number of rail systems no longer
adopt methods of operation which assemble train sets when the wagons are carrying
sophisticated goods (carriage of bulky raw minerals is a common exception). Other
rail systems purposely utilize good quality wagons and/or procedures of operation
to significantly mitigate shunting loads. These strategies are intended to minimize
shock severities for sensitive equipment such as electrotechnical equipment.
Relatively little of the data reviewed have been available in electronic form. To
permit comparison a quantity of the original (non-electronic) data have been manually
digitized in this techical report.