Dynamic Brakes

[rlkimbal]

I just discovered Open Rails after watching a video on 'At the Railyard'. I am generally pleased with it, but there are definite problems with the Dynamic Brakes. Leaving Bluefield on Austin Yoder's excellent East River route with an intermodal train in D8, I was doing 19 mph at the highway overpass bridge at East Bluefield with MSTS. With Open Rails I wa doing 31 mph. Having worked in Operations Research at NS and as a locomotive engineer I know MSTS is much closer to real life. A SD70 or Dash9 with High-Capacity Extended Range Dynamic Brakes should be putting 900+ amps into the giant toasters called dynamic brake grids at 25 mph. Open rails is no where close.

[mikeebb]

I've noticed that too. Dynamics in OR are weak no matter what you're running. Perhaps something to research and fix in 1.0? Also, the commuter and regional Amtrak trains I've been on have fairly powerful braking - probably dynamic - well before there's any sound of air use.

Of course, there are some activities even in MSTS where the default locomotives don't have *any* dynamics even though they should. Not sure which activity-related config file does that...

Another question peripherally related for the OR folk: in the 'single handle' control for power & dynamics, does the 'real thing' have some kind of a detent or stop at the zero point? Sort of like with a car you have to push a button or push down on the lever or whatever to go past that point? If so, could that be simulated by something like when you get to zero throttle you have to release the keyboard button (or whatever) then press it again to go into braking setup? It's kind of a pain where if you're coming out of the throttle you go right into dynamics setup, then can't get out until all of the timeouts are done. Yes, I know MSTS doesn't have that either - more a question whether 1) there something prototypical that does this, and 2) if there is, could we simulate it in some simple way?

[UP_4848_Thunder]

Would be nice to hear what version because I remember when that was an issue and so far with the experamental releases, I see the problem fixed more then what it used to be since before ORTS was reading the eng file dynamic speeds as MS instead of MPH.

[rdamurphy]

I'll take a look at the Dynamic Brake code this weekend and see if I can come up with an answer for you...

Robert

[rlkimbal]

Thanks. I am using version 0.9.0.1648

[baldwin]

I think you will find that the dynamic brakes have been fixed since version 0.9 was released. Go to http://openrails.org/experimental.html and download the file OR_X.zip. This will give you version 1831 instead of the 1648 you are currently running.

[rlkimbal]

I am sorry. I just installed and ran version 1831 and I am getting the same speed. Amps are showing zero.

[rdamurphy]

Can you give me the specific route, location, and locomotive?

Reading through the OR forums, it seems part of the problem is that the MSTS Dynamics were so whack that a lot of people tweaked them by entering totally off the wall numbers in the .eng files. OR is using more close to real world numbers, so the Dynamics come out weak as a result.

It may be something that will have to be fixed locomotive by locomotive...

We've run into this exact same problem in several areas, including the exhaust and steam/smoke area.

Robert

[OTTODAD]

Are dynamic brakes in MSTS locos also functioning in helpers of long and heavy freight trains, forinstance running down the Cajon Pass, which is not being displayed by the 3 ORTS F5-Hud options ?

[rdamurphy]

The F5-Hud clearly shows that dynamics are working on all units. Using default D-9's on Don Karch's Rollins Pass route using locos up front and 2 in the rear with 50 loaded tank cars:

Open Rails 2013-10-28 09-06-27.jpg

Robert

[PORU333]

Dynamic Brakes, what are those?
The railroad I grew up, only uses train and locomotive braking, dyno's disabled.

[OTTODAD]

The F5-Hud clearly shows that dynamics are working on all units.

Where in these 8 DASH-9 used by my Monster consist do the 5 F5-Huds show that all of them are using Dynamic Brakes ?


.

[rdamurphy]

Dynamic brakes work on feedback from the traction motors. In other words, there is amperage generated by the traction motors themselves, which is dissipated through the dynamic brake grids, which are giant resistors, through heat.

They generate no current unless they're rolling, and dynamics don't work below 8 mph (for extended range dynamics.)

Your screenshot clearly shows the train is going 0.0 mph with a 36% brake application...

I'm not sure why you would post this, when it shows OR doing exactly what it's supposed to be doing?

Robert

[OTTODAD]

I know little on the subject of locos physics and am curious whether applying Dynamic Brakes in an MSTS 8 locos freight train applies them in all of its 8 locos.

So I have created an activity which runs my monster freight train down the Cajon Pass 4 towards Bernardino where a similar train, some of its brakes failing, derailed in the curve just before its station yard.

http://en.wikipedia.org/wiki/San_Bernardino_train_disaster

Where in this screenshot of the 5 ORTS F5-Huds can I see that the Dynamic Brakes in all 8 locos are functioning, the train with no train brakes applied as yet gathering speed slightly with 50% Dynamic Brakes applied ?


.

[eric]

In real life, if they're MU'd and equipped, DBs are engaged on all traction motors. If you're seeing acceleration at 50pct, increase the DB a notch or two. There's more resistance needed for that weight.

The -KW on locomotive info HUD shows they're engaged.