[Weter]

They DO dump air, as You said, but at non-EP application: i.e. Apply and Emergency modes; as soon as BP pressure starts drop with defined tempo, slightly higher, than normal application (none by the electric impulse).
Making actuation of brakes at each car more soon, more synchronous along the consist, rather "braking wave" can make, being propagated from head of the train to tail, as if BP discharged through driver's valve on locomotive only.
Else, it accelerates discharge of BP in emergency mode.
So, as You can see, this latter function is opposite to Softness tempo discharge, which means that brakes are not actuated, when pressure drops very slowly.
But both are NOT EP.

All non-EP functions are working quite right now under ORTS, thanks to Cesar.
The problem is EP combination.

[darwins]

As far as I can tell there are basically 7 different types of electrically or electronically controlled brake systems. In OR I believe only #1 and #2 are working well at present. You would like to see #3 added and I would like to see #4 added.

( EP ) Electro-Pneumatic

1. Air Twin Pipe EP, Brake pipe pressure does not drop during normal EP operation.
Auxiliary reservoirs are charged from main reservoir pipe.
Currently supported in ORTS using BrakesTrainBrakesType ( EP ) and brake controller tokens:
TrainBrakesControllerEPHoldStart
TrainBrakesControllerEPFullServiceStart
TrainBrakesControllerEPOnlyStart

2. Air Twin Pipe EP, Brake pipe pressure drops during normal operation.
Auxiliary reservoirs are charged from main reservoir pipe.
Currently supported in ORTS using BrakesTrainBrakesType ( EP ) and brake controller tokens:
TrainBrakesControllerEPApplyStart
TrainBrakesControllerSelfLapStart
TrainBrakesControllerHoldLappedStart
TrainBrakesControllerFullServiceStart
TrainBrakesControllerFullServiceStart

3. Air Single Pipe EP, Brake pipe pressure does not drop during normal EP operation.
Auxiliary reservoirs are charged from the brake pipe.
Not currently supported in ORTS

4. Reservoir Pipe only EP, (3-step brake and pulse modulated brake) no brake pipe.
The brake pipe is replaced by a train wire - energised = normal EP - dead = emergency brake application.
Auxiliary reservoirs are charged from main reservoir pipe.
Not currently supported in ORTS, but TrainBrakesControllerEPApplyStart and TrainBrakesControllerEPOnlyStart tokens give an approximation.


( SMEE ) Straight air Motor and Emergency Electro-pneumatic

5. Straight air pipe provides air directly to brake cylinders during normal EP application.
*** Does straight air pipe pressure drop during normal EP release? ***
The brake pipe (emergency pipe) and auxiliary reservoirs are only used during emergency braking.
Not fully supported in ORTS but BrakeSystemType ( "SME" ) provides a good approximation.
There are currently no tokens to distinguish SMEE (electro-pneumatic) operation from standard SME operation.
The available brake tokens are:
TrainBrakesControllerSMEReleaseStart
TrainBrakesControllerSMEOnlyStart


( EV ) Electro-Vacuum

6. *** Does brake pipe vacuum drop during normal EV operation? ***
Auxiliary reservoirs are charged from the brake pipe.
This system is not currently supported in ORTS.


( ECP ) Electronically Controlled Pneumatic Brake

7. Air Single Pipe ECP
Engineer has remote (wireless) control over brake cylinder pressure for each individual wagon in a long freight train.
*** Does the engineer also control the brakes by changing the brake pipe pressure from locomotive(s), power unit(s) and EOT? ***
ECP exists as an option in ORTS, I am not sure what the degree of functionality is.


Questions

*** Does straight air pipe pressure drop during normal EP release? ***
At present I do not have full details of SMEE operation or other SME EP brake operation. I seems logical that the straight air pipe would remain charged during EP operation, and that brake cylinders would either charge by electric operated valve from the straight air pipe during application, or discharge directly to the air by electric operated valve during release, without the need to drop the pressure in the straight air pipe. It would be good to confirm this. Can anyone get a copy of any relevant technical documents such as:
The "SMEE" electro-pneumatic self-lapping and automatic emergency brake equipment
"SMEE" Brake Equipment With ME-42 Brake Valve - 1950
Detailed document from a railway in Australia that uses this equipment
Technical documents from railways in Japan that use similar equipment (preferably with English translation!)

*** Does brake pipe vacuum drop during normal EV operation? ***
Logically the vacuum in the brake pipe could be maintained during normal EV operation. Electric operated valves are presumably used to admit atmospheric air directly to the brake cylinder during brake application, with the vacuum in the brake cylinder being restored from the train pipe when the valve was closed. This would be similar in operation to the Air Single Pipe EP system. There seems to be very little information available, there is possibly a description given in "Electric Trains, Their Equipment and Operation" by W A Agnew. This system was mainly used in South Africa. So further information or technical documentation from South Africa would be needed.

*** Does the engineer also control the brakes by changing the brake pipe pressure from locomotive(s), power unit(s) and EOT? ***
It logically be possible for the brake pipe to remain fully charged whilst brakes on individual wagons or groups of wagons are applied or released. This would make the system similar to the Air Single Pipe EP system. Possibly someone from USA can provide more detail or some technical documentation.

[Weter]

Hello.
If you meant my case under #3, it should be added, that it cAn work as usual Air Single Pipe, if EP is turned off, failed, or if driver uses valve positions APPLY(discharge of BP at full service tempo through driver's valve) or EMERGENCY (discharge of BP with fastest tempo through driver's valve, plus by every distributor as an addition)
And indeed, it will actuate brakes as usual single pipe auto brake system in case of train tear-up, or if any of stop-valves will be engaged at any carriage.

[darwins]

Weter, on 15 February 2022 - 06:50 AM, said:

Hello.
Why at 2-nd example full service token mentioned twice?

My mistake. http://www.elvastower.com/forums/public/style_emoticons/default/sign_oops.gif

Quote

If you meant my case under #3, it should be added, that it cAn work as usual Air Single Pipe, if EP is turned off, failed, or if driver uses valve positions APPLY(discharge of BP at full service tempo through driver's valve) or EMERGENCY (discharge of BP with fastest tempo through driver's valve, plus by every distributor as an addition)
And indeed, it will actuate brakes as usual single pipe auto brake system in case of train tear-up, or if any of stop-valves will be engaged at any carriage.

This is also true for #1, #5 and #7 (probably also for #6 too). Normal operation can use Air_Twin_Pipe or Air_Single_Pipe or SME or Vacuum_Single_Pipe as appropriate. Then the normal tokens will work.

EP needs special tokens to allow the EP brake valves on the cars to respond more rapidly and possibly also differently to normal air brakes. For example older EP brakes of type #1 allowed graduated release when using EP (as this was done with the EP valves) but when working with the regular air brake then graduated release was not possible as the cars were fitted with standard triple valves.

[Weter]

And one more addition: this is for one locomotive to be able to work with both types of systems: EP and Single Pipe; also, non-EP equipped cars can be coupled to the rear of EP-equipped train and be braked by regular BP discharge. Same for game: large amount of old carriage models from MSTS era was AirSinglePipe, because EP didn't guarantee full release. But if ORTS would allow to use combined system properly, it might be possible to use all models together.

So, for now, defining for one car/locomotive both systems ("AirSinglePipe" "EP") doesn't work now, but I didn't test Distributor yet, however.

Hence, two questions:
-what is correct definition for given case (if possible)?
-ask to try implement/correct program to do so.

[darwins]

Weter, on 15 February 2022 - 12:04 PM, said:

And one more addition: this is for one locomotive to be able to work with both types of systems: EP and Single Pipe; also, non-EP equipped cars can be coupled to the rear of EP-equipped train and be braked by regular BP discharge. Same for game: large amount of old carriage models from MSTS era was AirSinglePipe, because EP didn't guarantee full release. But if ORTS would allow to use combined system properly, it might be possible to use all models together.

So, for now, defining for one car/locomotive both systems ("AirSinglePipe" "EP") doesn't work now, but I didn't test Distributor yet, however.

Hence, two questions:
-what is correct definition for given case (if possible)?
-ask to try implement/correct program to do so.

This is all not yet possible.
It is all wishes for the future.

I don't think it will work at all now, not unless perhaps part of it works if defined as 'ECP'.

[Laci1959]

Hello.

We use two single-wire brakes on narrow-gauge railways. One is the conventional single-wire (Air_single_pipe), the other single-wire is a pressurized brake that acts directly on the brake cylinder of vehicles. The locomotive brake (Brake_Engine) controls the pressure in all cars. This prevents the auxiliary air tank of the wagons from running out on a long slope.

It would be good if it happened one day.

Sincerely, Laci1959

[Weter]

It sounds as straight-actuated brake.
Didn't You try that one, Peter implemented?

Locomotives here have third pipe (beige colored) which is engine brake pipe.
This allows to control brakes of all MU-ed locomotives by independent brake valve of leading cab.

[darwins]

Laci1959, on 17 February 2022 - 08:35 AM, said:

Hello.

We use two single-wire brakes on narrow-gauge railways. One is the conventional single-wire (Air_single_pipe), the other single-wire is a pressurized brake that acts directly on the brake cylinder of vehicles. The locomotive brake (Brake_Engine) controls the pressure in all cars. This prevents the auxiliary air tank of the wagons from running out on a long slope.

It would be good if it happened one day.

Sincerely, Laci1959

The system described is known as the Westinghouse-Henry double brake. For many years it was used on the PLM (Paris-Lyon-Mediterranée) main line in France for the same reason - you can not run out of brake power on a long descent.

At the moment there is not a fully functional version of the Westinghouse-Henry double brake in ORTS. As Weter says, Peter has made a simple model of a similar system, the SME (Straight-air, Motor and Emergency) brake system. The SME and the electric controlled SMEE were used on subway systems in USA, railcars in Australia and many trains in Japan.

These are the brake sections from Peter's Australian dmu:

Comment ( ******************************* Brakes *********************************************
            	Included in this section - Type, Force, Reservoir, Application, Release. etc
     	************************************************************************************ )

BrakeEquipmentType ( "Triple_Valve, Auxilary_reservoir, Handbrake" )
BrakeSystemType ( "SME" )
MaxBrakeForce ( 115kN ) Comment ( * braked approx 80%, CoF 0.38 * )
MaxHandbrakeForce ( 30kN )
EmergencyResVolumeMultiplier ( 1.0 )
TripleValveRatio ( 2.5 )
MaxReleaseRate ( 10.0 )
MaxApplicationRate ( 25.0 )
MaxAuxilaryChargingRate ( 20.0 )
EmergencyResChargingRate ( 20.0 )
BrakeCylinderPressureForMaxBrakeBrakeForce ( 45psi ) Comment ( straight air pipe max pressure = 45 psi )
EmergencyResCapacity ( 2.064ft^3 )
BrakePipeVolume ( 0.58ft^3 )

ORTSBrakeShoeFriction ( 0 0.380 10 0.364 20 0.349 30 0.335 40 0.321 50 0.309 60 0.297 80 0.276 100 0.259 120 0.245 140 0.235 160 0.228 200 0.224 ) 
Comment ( Composite brake shoes - data based on CoFren )

Comment ( ************************** Brake System *********************************************
                  	Included in this section - Compressor, Reservoir, Application rates, etc
     	************************************************************************************** )

Comment ( *** Braking system *** )

BrakesTrainBrakeType ( "SME" )
BrakesEngineControllers( "Train" )

Comment ( == Compressor, Reservoir and General == )
AirBrakesMainMaxAirPressure( 105psi )
AirBrakesCompressorRestartPressure( 80psi )
ORTSBrakePipeChargingRate ( 150 )
AirBrakesMainResVolume( 16ft^3 )
ORTSMainResChargingRate ( 0.575 )
TrainPipeLeakRate ( 0.0833 )

Comment ( == Automatic Brake valve - Train == )
TrainBrakesControllerMaxSystemPressure( 65psi )
TrainBrakesControllerMaxReleaseRate( 12.0psi/s )
TrainBrakesControllerMaxApplicationRate( 6.0psi/s )
TrainBrakesControllerFullServicePressureDrop( 20psi )
TrainBrakesControllerMinPressureReduction( 1psi )

Brake_Train ( 0 1 0.09 0.30
NumNotches ( 3
Notch ( 0.0 0 TrainBrakesControllerSMEReleaseStart )
Notch ( 0.2 1 TrainBrakesControllerSMEOnlyStart )
Notch ( 1.0 0 TrainBrakesControllerNeutralHandleOffStart ) ) )

EmergencyStopToggle( 0 1 0 )

Brake_Train controls the straight air pipe that sends air directly to the brake cylinders.

At the moment, for the SME system, there is no brake valve for the normal air brake pipe, only the emergency valve.

For the Westinghouse-Henry system there should be a separate brake valve for the Westinghouse brake pipe rather than just an emergency valve.

I think generally the Westinghouse brake was used for normal service stops and the straight air brake for controlling the train when going down the hills.

[Laci1959]

Hello.

Quote

The system described is known as the Westinghouse-Henry double brake. For many years it was used on the PLM (Paris-Lyon-Mediterranée) main line in France for the same reason - you can not run out of brake power on a long descent.

I have more to learn.

Quote

For the Westinghouse-Henry system there should be a separate brake valve for the Westinghouse brake pipe rather than just an emergency valve.

We have two brake valves. One is the locomotive brake (EngineBrakesController), it has no emergency brake position. He has three jobs. Release Hold Braking. As long as Braking is on, it increases the cylinder pressure. When in the Hold position, hold the pressure. The older ones simply shut off everything, meaning it didn’t make up for the leaking air. The current ones are keeping up the pressure. In the release position, it releases air. Railroad slang calls Jancsi ( John is nicknamed or the child is John ) a brake.
Studying the code, this should be the SME brake.

It's almost like I thought. Cab also made for it?
If you could assign the automatic brake to TRAIN_BRAKE LEVER and the SME brake to ENGINE_BRAKE LEVER, it would be perfect.
But if it’s the other way around, it’s okay, I just know how to assign it.

Sincerely, Laci1959