The Tractive Effort and Train Resistance (R) numbers printed on the bottom of the Train-Consist actually mean something and are real numbers.   

Just to recall:  Tractive Effort is what the locomotive can pull. Train Resistance is what it takes to pull the cars presently assigned to the train on the ruling (~steepest) grade (between train reporting points).  Tractive Effort should exceed Train Resistance.

In ProTrak tractive effort is calculated as the engine weight (in oz) times the adhesion.   (You entered a unit's model weight and the adhesion.  If no adhesion value was entered, 10% is used.)   

In ProTrak train resistance is calculated from a car's rolling resistance (default value 1%), the curve resistance (based on your minimum mainline radius, the value being typically 0.5%) and the track grade.   Grade is entered at "Stations".   These total rolling resistance values are added up for all the cars in a train - plus the locomotive.

In ProTrak a "scale correction" is applied to both TE and R to convert from "model ounces" to "prototype pounds" (lbs).  For HO the scale correction is a little over 50,000 and for "N" is much, much higher.  Thus on the Train-Consist you see TE and R in lbs - with values that both mean something and are near prototype values.

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At the last operating session it was noticed that some of the R values did not make sense - given the grades on the railroad.   Digging down I found that the "Train Route Segments" values were not correct.  ProTrak finds the ruling (steepest) grade for each segment of train's route.  That is, between train reporting points the ruling grade is calculated and recorded.  You can see the values for your railroad at "Transportation/Operations Diagnostics", then the menu item "Show/Train Route Segments".

This listing is by "Train", "Segment Number", "Grade" (ruling uphill), "Buff Grade" (ruling downhill), "Base Station" (where the grade starts) and "Top Station" (where the grade crests).

Added in ProTrak- 359 are the "Recalculate" and "Print" buttons.   The listing as initially displayed is the >recorded< data (as calculated the last time the FP ran). "Recalculate" updates the route segments, for any new data.

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From the train-route-segments listing I could see that the "station grade" numbers discovered were not correct.  I corrected the station grades and in doing so added some items to make that easier.

The "station distances", the "station grades" and the "station elevations" are interconnected as "elevation = distance times grade".  Prior to 358 if one value was changed one of the other values was corrected.  I have added checkboxes "Fix" opposite each of the 6 datafields for distance, elevation and grade.  You click "Fix" for two of the data (for each of the "interval" or the siding") and the third value will be adjusted.

Also, prior to 358/359 the program automatically adjusted the elevations of all stations to the >west< of the station you just updated.  (This was to keep 'things' consistent and so you didn't have to change 40 stations if you changed one station at the east end.)  With 358/359 there is now a checkbox to activates this automatic check.   Now you can go into any one station that you have just measured and enter its data, without messing up the data you entered yesterday.

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Train-consist <= Train resistance <= Train Route Segments <= Station grade data.

OK?

               Jim