8 Scenarios

A scenario combines a train model, a set of national values, a track profile and optionally a normal service brake model in order to determine braking distances and supervision limits. It also includes some additional parameters, see below.

8.1 The Scenario Panel

It is possible to compare two scenarios A and B, that may differ in any kind and number of parameters. All data of the scenarios A and B are stored in the scenario file (extension .scn). A scenario file that has not been saved after the latest modification is marked with an asterisk ’*’ in the title in the tab pane.

All data related to the scenarios A and B is entered in the upper part of the scenario panel, shown in figure 13.


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Figure 13: A scenario panel


The lower part of the scenario panel shows calculated results in two tables.

8.1.1 Parameters

This section shows all parameters that are necessary to evaluate a scenario or to compare two scenarios, which do not belong to a train model, a normal service brake model, a set of national values or a track profile.

Scenario A

Select a train model, a set of national values and a track profile out of the available project members. If you want to calculate a guidance curve, select a normal service brake model as well. Remember that you can select only project members in the same package as the scenario or in the global package.

If you select a fix train model, you’ll have to select one of the brake models by its BMI. If you don’t state a valid BMI, the brake model with the highest BMI (i. e. the master brake model) will be selected automatically.

Acceleration and brake pressure

According to [Subset 026-3] the measured acceleration will be used for determination of the EBI. You can enter a value greater than zero if this seems probable in reality.

The brake pressure will be used to adapt the service brake build-up time, but only if the brake feedback interface is available according to the train model and allowed according to the national value Q_NVSBFBPERM.

Speed inaccuracy

Define which speed under-reading amount shall be assumed in calculations. If ”Subset-041” is selected, the under-reading amount is assumed to be the allowed value according to [Subset 041], 5.3.1.2. If ”Fix” is selected, the value stated here is used for any speed.

Distance inaccuracy

Define which distance under-reading and over-reading amount shall be assumed in calculations. If ”Subset-041” is selected, the absolute and relative under-reading or over-reading amount are assumed to be the allowed values according to [Subset 041], 5.3.1.1. If ”Other” is selected, you can state another absolute and relative inaccuracy.

The relative inaccuracy always relates to the distance from the LRBG. Therefore the balise group locations given in the track profile have significant impact on the release speed(s) (if calculated on-board) and the limits typically.

Scenario B

If you want to compare two scenarios, select the related parameters as for scenario A.

Calculation parameters

These parameters only affect the ”Limit locations” table in the lower part of the scenario panel. They have no impact on the limits chart described in section 8.2.

Select the minimum and maximum train running speed for whose to calculate limits, and the speed step size.

8.1.2 Result

This section will show the results calculated after pressing Calculate – Calculate Scenario Limits or the corresponding button.

Reference Location

The reference location of the results can be selected to be

Data Selection

The release speed data and the locations can either be shown for scenario A, scenario B or the difference between B and A.

Release speed(s)

If the release speed is determined by trackside, the release speed monitoring (RSM) start location will be calculated and indicated here.

If the release speed is calculated on-board, a release speed will be calculated at the perturbation location and at each further balise group. All release speeds and the corresponding start locations will be shown here.

Limit locations

The calculated limits according to the reference scenario and the calculation parameters (see above).

8.2 Limits Chart Window

If you press Calculate – Show limits chart or the corresponding button, a chart window will open, showing the limits graphically.


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Figure 14: A limits chart window


All axis can be scaled and zoomed.

The presented graphics can be exported to a vector graphic (.svg) or a bitmap (.png) file, select File – Export ... in the menu of the chart. Note that in vector graphics format, the graph data is exported with original resolution, so a later printout will have a very high quality (if not reduced by the later processing).