[Weter]

Oh, my God: 22 valuable pages!
Darwins, I'm putting my hat off.

Our 334 brake valve of old EMUs looks like a copy of Westinghouse's one:
http://trainsimpack.ucoz.ru/KM/334_1.jpg
As you can see, MRP is painted blue, BP-red.

Quote

Driver’s Valve No. 394
Train brake – automatic air brake has graduated release (?) (but is not self-lapping).
394 do not have graduated release.
395 does (at the EP part),
Both are not self-lapping
Actually has 7 positions, 4 notched
I. Release &BP Charge
Brake pipe connected to Main Reservoir and ER too, thru 1,6mm gicleur-for more slow pressure rising
TrainBrakesControllerOverchargeStart seems good
II. Running (&release)
Brake Pipe pressure controlled by Eq Res - creates and maintains working pressure in brake pipe - releases both train and locomotive brakes.
BP & ER pressures BOTH are controlled by adjustable reducer for feeding and by stabilizer to drop excessive pressure(if any)
Loco brake is released only if 254 valve(independent brake) is at release position.
TrainBrakesControllerReleaseStart.
III. Lap without BP feeding
ER and Brake Pipe isolated connected. ER pressure equalizes with BP. Pressure may drop slowly due to leakage.
TrainBrakesControllerHoldLappedStart
IV. Lap with BP feeding (Pressure Maintaining)
Maintains Reduced pressure in brake pipe against leakage.
<token is missed> I would to offer
TrainBrakesControllerSelfLapStart
VA. BP discharging BP in "soft" rate. (Slow Service)
Allows air to escape from brake pipe more slowly than normal service application rate. For preparing triple walves af all cars in long trains for simultaneous actuating, avoiding wave-like brakes applying, which could stress couplers "Soft" rate of discharge.
Not currently available in OR
V. Service
Allows air to escape slowly from brake pipe at normal service application rate.
TrainBrakesControllerFullServiceStart
VI Emergency
Rapidly releases all air from brake pipe.
TrainBrakesControllerEmergencyStart

Maybe additional corrections are needed, but goodnight at this time

[steamer_ctn]

 darwins, on 09 November 2020 - 07:28 AM, said:

I have tried to survey a variety of brake controllers that might be used in Open Rails and listed them in the attached document.

Darwin, this is an excellent summary, and no doubt will be a useful reference document.

Just to confirm our understanding.

Is each existing brake token unique in its functionality, and therefore where it is used in a different brake configuration, the expectation would be that it would perform in exactly the same way?

In other words we are not expecting a brake token to behave slightly differently depending upon which brake configuration it is used in. Is this correct?

Thanks for your work on this.

[darwins]

 steamer_ctn, on 09 November 2020 - 10:07 PM, said:

Darwin, this is an excellent summary, and no doubt will be a useful reference document.

Just to confirm our understanding.

Is each existing brake token unique in its functionality, and therefore where it is used in a different brake configuration, the expectation would be that it would perform in exactly the same way?

In other words we are not expecting a brake token to behave slightly differently depending upon which brake configuration it is used in. Is this correct?

Thanks for your work on this.

Yes - as far as I can tell so far. If anything there may be the reverse problem of two or more brake tokens possibly giving identical performance. As Weter has pointed out there is no obvious difference between TrainBrakesControllerFullServiceStart and TrainBrakesControllerApplyStart [edit - TrainBrakesControllerFullServiceStart - reduces ATP pressure at the service rate until the full service brake pipe pressure is reached / TrainBrakesControllerApplyStart - continues to reduce pressure at the service rate until the brake pipe pressure is zero], also from a simulator point of view it seems that TrainBrakesControllerNeutralHandleOffStart and TrainBrakesControllerSelfLapStart and TrainBrakesControllerRunningStart can be interchanged - although there is obviously a difference in real life function and a need to have different notches on some controllers.
It is still a work in progress because (i) I can not test the overcharge function until it appears in an unstable version (ii) I am hoping for input from other countries to know if there is anything significantly different - Spain, Italy, France, India, Japan - in particular may have variations - although a lot of Japanese stuff is now based on the SME / SMEE framework which is not yet possible in OR. The bottom line seems to be with one or two more tokens that most things will be possible.


I am waiting for the overcharge function to appear in the unstable version.

[Edit - although TrainBrakesControllerNeutralHandleOffStart is behaving the same as TrainBrakesControllerSelfLapStart and TrainBrakesControllerRunningStart - this does not seem correct - the brake descriptions say all ports closed for neutral - so ATP pressure should fall due to leakage and therefore TrainBrakesControllerNeutralHandleOffStart should behave the same as TrainBrakesControllerHoldLappedStart.]

[Weter]

@ Darwins:
1. is list of Engine (independent) Brake Controllers ( or addition to previous list) planned?
2. what ATP means (train pipe A, but what is "A"?)

Quote

we are not expecting a brake token to behave slightly differently depending upon which brake configuration it is used in. Is this correct?

I think, the ideal situation, is when the tokens itself are similar, and differences(if needed) are referenced by separate parameters-as we have now with, for example, the set of pressure differences rates.

[darwins]

I could add engine brake controllers - some are included in the list where they are part of a brake system - generally they are simpler than train brakes and it seems unlikely that additional tokens will be needed to model them.

If anyone has any interesting examples I will be happy to look at them.
Sorry, also need to explain abbreviations - ATP = air train pipe

[Weter]

Oh, yes: from Rudolf Richter's *.eng Manual we can see, that all brake tokens are applicable to both: Train and Engine brakes.
But in case of 254 controller, there is I-st "while pressed" position for bailing-off locomotive(s) brakes when train brakes are applied.
It seems, today MSTS/ORTS lever-style cab controls can't have "while pressed" positions (only buttons/two states can) and engine brake levers can't control bail-off function (it only can be assigned to buttons, again) Also, PneumoBrake can't be actuated at last positions of combined control, assigned to throttle/dynamic brakes management, to substitute faded Dynamic brakes at lowest speeds for bringing the train (more often tram or EMU) to complete stop.

What is distinction on using ATP abbreviation instead ob BP?
What in case of twin-pipe systems? Isn't it confusable?

[darwins]

No difference between BP and ATP for air braked trains. BP could also be the vacuum brake pipe on vacuum braked or dual braked trains.
On twin pipe system ATP is the brake pipe and MRP - Main Reservoir Pipe is the other one.
There are two while_pressed buttons available so far
The exhauster fast speed button on diesel and electric locos with vacuum brakes (J key) now works while pressed but I did not know the bail off does not work from cab view (as it is does not exist on any trains I normally drive!) - so another problem with bail off.
The old MSTS engine brake tokens still apply, but some of the new OR train brake tokens may not have an engine brake equivalent.

[Weter]

Oh, I've just forgot about vacuum brake systems, sorry. Now I see.
Are ORTS tokens already exist, or only planned?
I think, the button- does work (/ key), but I meant the possibility to bailoff by pressing "[" when EB lever of 254 valve is at II position (wich could cause the handle to move to I position, then return to II, as soon as the "[" key is depressed).
Could You explain to me, what does "sprung" mean in context of brake levers description in *.cvf-files? (I didn't encounter that anywhere inside *.eng-files, so it possibly applied to animation only?)

[darwins]

Sprung - which you will find in some cvf files means what you describe above - the switch / control moves when you push the key - then goes back when you release the key.

There are only a few available at the moment - like the whistle or horn - in the cvf file you will see something like this using WHILE_PRESSED

    	TwoState (
    		Type ( HORN TWO_STATE )
    		Position ( 138 373 28 28 )
    		Graphic ( ..\\..\\common.cab\\em1-em2\\horn1.ace )
    		NumFrames ( 2 2 1 )
    		Style ( WHILE_PRESSED )
    		MouseControl ( 1 )
    	)

You can only use this for things that have been put in the OR code to work that way. In the eng file it looks just like any other controller.

[Weter]

There is "pressed" option as well
OTOH, somewhere (maybe KIHA 31 or Golsdorf 380?) I've seen sprung/not sprung options indeed for brake levers IIRC, but it was nearly 20 years ago...

Position I is sprung to II position and it bails EB off:
https://www.dieselloc.ru/images/tormoznoe-oborudovanie-lokomotivov/tormoznoe-oborudovanie-lokomotivov-34.jpg

Add:
So brake levers can't have such While pressed positions...
I can see only fixed/notched, referred by zero and Continious/unnotched, referred by 1 in *.eng-file