[markus_GE]

Csantucci, on 26 June 2015 - 06:22 AM, said:

[...] I found engmod also at trainsim here http://www.trainsim....earchid=5078828 and downloaded it.
[...]

"No search results", because the link to the list generated by a search is only valid for a certain time. Please post the file name at TS instead :thumbup3:

Cheers, Markus

[Csantucci]

I found it by entering "engmod" in the "text" field, selecting among the MSTS Utilities.

[Genma Saotome]

James Ross, on 25 June 2015 - 01:47 AM, said:

What we will do is log a warning and correct the value inside the game (we do this for a variety of things already).

I know that is done for missing textures but I'm unaware of anything else. Is there a list somewhere?

[R H Steele]

markus_GE, on 26 June 2015 - 07:13 AM, said:

"No search results", because the link to the list generated by a search is only valid for a certain time. Please post the file name at TS instead :thumbup3:

Cheers, Markus

Marcus, in my post.... engmod20.zip at TS

also...many of us who are still new to all this are confounded by all the knowledge needed to make the required changes. There is a ten year history of everyone doing "who knows what" to engine and wag files. Work-Arounds, tricks, gimmicks, call them what you will - features or bugs - the majority of rolling stock (and this includes some payware also) is an inconsistent hodge-podge.
For instance there are many boxcar packs that have 5 brackets after the light section....result... the brake values do not appear in the F5 brake HUD....removing the light section with RR still leaves the extra bracket, so nothing for it but to remove it manually. How many people are going to do that?
Of course, along the way there are a few who knew what to do and make files with appropriate data. But knowing which is which is just plain daunting at times.

First time RouteRiter offered a choice of iron or composition brakes sent me on an hours long research journey and I still do not know if I got it right. (I chose composition..they were contemporary wagons)

[dcarleton]

Csantucci, on 24 June 2015 - 12:01 AM, said:

So e.g. at trainset load time OR could test if AirBrakesCompressorRestartPressure is at least 20 above TrainBrakesControllerMaxSystemPressure and AirBrakesMainMaxAirPressure is at least 5 above AirBrakesCompressorRestartPressure, and if not, it could correct them. The possibility of manually hard-modifying the .eng file appropriately rising the two parameters would remain and in this case of course OR would not intervene with the runtime correction.
That would be a simple OR code modification. What do OR users think about this?

Yes. Do this.

[Csantucci]

Blueprint here https://blueprints.l...n-of-eng-params .

[longiron]

My concern about OR using override default values are the default values themselves - what's correct? Depending on the era, geography and train type, the CORRECT values are different. Here's a portion of an article by Al Krug, a respected locomotive engineer and prolific writer. And this is just for North American railroads -- http://www.railway-t...om/brake2.shtml#

Long ago, like in the 1920s, the brake pipe was 70 psi. That was fine for the 40 ton cars of the day. By the 1940s the coal cars had grown to 55 tons and the brake pipe pressure pushed to 80 psi. In the 1950s the cars were 70 tons and in the 1960s had grown to 100 tons. Still 80 psi brake pipe pressure handled the braking chores OK. By the 1970s coal & grain cars had climbed to 135 tons and the 80 psi brake pipe had little margin for error. On unit coal trains of 15,000 gross tons, even on 1.25% grades. The emergency stop distances for heavy trains was growing longer and longer.

During the 1970s our railroad rules dictated an 80 psi brake pipe for all trains EXCEPT loaded unit coal and grain trains which were to use 90 psi. This shortened emergency stop distances for these heavy trains but created other problems. For instance when the trains were unloaded the pressure had to be reduced. If a coal train using a 90 psi pressure gave cars during switching operations to a freight using an 80 psi brake pipe, the "over charge" condition had to be reduced. This didn't always get done properly resulting in stuck brakes on some cars and over heated wheels. As the weight of lumber, tank, and other cars caught up to the coal and grain cars and load/empty sensors were applied the railroad simply mandated a 90 psi brake pipe for all trains. However, railroads that don't operate unit coal trains or don't have steep grades still use 80 psi since it is adequate for their type of operations. Some yard and transfer operations that operate at low speeds still use 70 psi, taking advantage of the shorter charging times.

And from wikipedia

The compressor on the locomotive charges the main reservoir with air at 125–140 psi (8.6–9.7 bar; 860–970 kPa). The train brakes are released by admitting air to the train pipe through the engineer's brake valve. A fully charged brake pipe is typically 70–90 psi (4.8–6.2 bar; 480–620 kPa) for freight trains and 110 psi (7.6 bar; 760 kPa) for passenger trains.

That was the whole purpose of ENGMOD and RR braking update: to do a mass update of WAG/ENG files with the correct parameters based on the ERA and TYPE of car.

chris

[Csantucci]

Hi Chris,
first of all, thank you for the very useful info you have provided.
I admit that there aren't values valid for all trainsets. However, when you have an engine like the original MSTS GP-38, that has
TrainBrakesControllerMaxSystemPressure( 90 )
AirBrakesMainMaxAirPressure( 90 )
AirBrakesCompressorRestartPressure( 87 )
almost everything increasing the second and third parameter is better than the original situation. And this is the aim of the correction.

Take into account that I don't set fixed absolute values for the second and third parameter, but I want that the difference between third and first parameter is higher than a minimum (and also that the difference between second and third parameter is higher than a minimum). So the correction is not based on absolute values, but on differences, and this should take into account the increase in pressure values that took place during time. I even am considering if taking into account not only a difference, but also a ratio.
There is another point, that is better explained by describing how the beta code works: at the moment a check is made if AirBrakesCompressorRestartPressure - TrainBrakesControllerMaxSystemPressure is > 25. If yes, things are left as they are. If no, AirBrakesCompressorRestartPressure is set to TrainBrakesControllerMaxSystemPressure + 35 (and AirBrakesMainMaxAirPressure is the maximum between AirBrakesCompressorRestartPressure + 5 and the actual value of AirBrakesMainMaxAirPressure). So the test threshold (25) is lower than the correction, that means that it is accepted that there are trainsets wich have only 25 as AirBrakesCompressorRestartPressure - TrainBrakesControllerMaxSystemPressure.
As told above, a check could be done that the entity of the correction (35) is not higher than, say, 40% of TrainBrakesControllerMaxSystemPressure.

[Genma Saotome]

You go poking around and hey, you learn something!

From Al Krug:

Quote

Brake Release

When I no longer need the brakes I can release them. This is done by moving my brake valve to the RELEASE & CHARGE position. As before, this simply connects the locomotive air compressors to the brake pipe and pumps air back thru the brake pipe raising its pressure back to 90 psi. The cars' triple valves sense that the brake pipe (90psi) is HIGHER than the reservoir (75psi) and move to RELEASE position. This connects the brake cylinder to the atmosphere, releasing the air pressure in the cylinder and thus releasing the brakes. It also connects the brake pipe to the reservoir to begin recharging the reservoir from the brake pipe. Notice there is NO GRADUAL release; the release is a complete release.

Now if memory serves, when I release brakes in OR and watch the numbers there is one column marked BC, which I always assumed was Brake Cylinder. It changes at about the same rate as the numbers in the AR column (assumed to be air reservoir).

If those assumptions are correct then what's going on with the brake cylinder in OR is completely wrong. Move the brakes into release and BC should change to 0 almost immediately. That should solve the problem of slow brake release.

[Mike B]

Please correct me, but from the way it behaves I think the BC value in OR is the locomotive (independent) brake cylinder, not the cylinders on each car. If you don't have any independent applied, BC goes to zero as the inverse of the AR pumping up. If you *do* have independent applied then BC only drops to the independent setting.

Brake release propagates back through the train as each car's triple valve gets the "signal" and changes, so brakes release up front well before the back on a long train. MSTS-Bin had a F5 view that showed the brake force per-car. While still not "instant" release for each car you could see the release (and apply) wave passing through the train. MSTS often did release brakes unprototypically fast; ORTS is probably more realistic, but can be annoying if you just want to "run trains" - hence the shift-/ initialization option that just releases everything. Sort of. I've found that if I don't finish releasing up front (e.g. AR is at maximum and front BP is at full release pressure) before initializing I will not get a full release for the train. So all "initializing" really does is cancel the release time for the rest of the train, which can be substantial otherwise.

I have no knowledge of the code involved. This is based strictly on observing behavior.