EP Brake - No partial release

[coolhand101]

Hi

Although OR supports the EP brake, i cannot get the brake to partially release.


I have this in the brake setup :

BrakeEquipmentType( "Handbrake, Triple_valve, Auxilary_reservoir" )
BrakeSystemType( "EP" )

and this in the Brake controller section :

Notch ( 0 0 TrainBrakesControllerReleaseStart )
Notch ( 0.10 1 TrainBrakesControllerEPApplyStart )
Notch ( 1.00 0 TrainBrakesControllerEmergencyStart )


The EP brake functions 100% for self lapping in applying, with air reduction from the main res pipe and with the brake pipe holding at its max pressure.

According to the Extended HUD Brake page, the EP brake ( triple valve ) status, remains in the lap position when moving the brake handle back for a partial release.

It appears the partially release for the EP brake may have been left out!

Can someone please confirm this ?

Thanks

[coolhand101]

If someone can confirm this, it means I haven't made a mistake my end!

Thanks

[baldwin]

Change the triple_valve to Distributor.

[coolhand101]

Change the triple_valve to Distributor.

Hi
Is that just an observation, or have you managed to get the E.P brake to partial release ?.

Thanks

[baldwin]

That is how a modern EP brake works. Single pipe with distributor.
The early pre WWII EP system used by the Southern region was a twin pipe with Triple valve system based on the Westinghouse brake.
From 1950 new builds on the Sothern were fitted with a superior system, still twin pipe but using the distributor with electrical control.
From 1970 on the next generation of EP moved to the single pipe and no reservoir, electrically controlled.

So, to be absolutely correct, until 1970 built units, twin pipe operation should be used. That may be where it is failing. Personally I use the single pipe with distributor on all electric stock.

[coolhand101]

That is correct. However in OR, no matter what settings, the brake will not partial release, when the brake type is E.P.
The other brake types 1P and 2P(haven't tried vacuum as yet) will partial release. If I could get this confirmed, it could well be a bug with the E.P brake type.

Thanks

[baldwin]

The problem is with your BrakeSystemType. That must be EP_single_pipe, or EP_twin_pipe with the corresponding twin or single pipe entries in the engine section of the file.

[coolhand101]

The problem is with your BrakeSystemType. That must be EP_single_pipe, or EP_twin_pipe with the corresponding twin or single pipe entries in the engine section of the file.

Thank you. I found no reference to EP_single_pipe, or EP_twin_pipe in the manual or anywhere else for this matter.
Just to confirm what you have stated :-

BrakeEquipmentType( "Handbrake, distributor, Auxilary_reservoir" )
BrakeSystemType( "EP_twin_pipe " )

and

BrakesTrainBrakeType( EP_twin_pipe )

Is this correct ?

Thanks

[baldwin]

Yes. Found by observation. All other brake types refer to single or twin pipe, so logically EP had to be the same. I changed one set of mine to EP just like yours and found the same as you, no lap when reducing brake pressure. I added the twin_pipe in my test case and got the behaviour you are looking for. Single_pipe will work the same. In fact, if you change the Triple Valve to Distributor along the whole train, you get self lapping EP style brake behaviour with straight air systems as long as the brake controller is set up right..

[coolhand101]

Yes. Found by observation. All other brake types refer to single or twin pipe, so logically EP had to be the same. I changed one set of mine to EP just like yours and found the same as you, no lap when reducing brake pressure. I added the twin_pipe in my test case and got the behaviour you are looking for. Single_pipe will work the same. In fact, if you change the Triple Valve to Distributor along the whole train, you get self lapping EP style brake behaviour with straight air systems as long as the brake controller is set up right..

I'm a little bit confused right now. There is no "EP_single_pipe" or "EP_twin_pipe token"? OR extended brake HUD, will just display a minus sign under the brake type.

Self lapping, i can already get under Air_single or twin.

I just needed confirmation that the "EP" brake token does not partially release, like the Air single or twin. Is that correct?

In case i'm missing something obvious that is staring me in the face, could you please post you "EP style" brake parameters ?

Thanks

[baldwin]

Nothing confusing about it. EP is exactly the same as a normal self lapping brake system with the exception of electric control. Electric control however is not modelled in ORTS far as I can see. No brake system can operate without having pipes defined in the eng file whether it be vacuum, air or EP. I do not see it as a fault or bug, just something that is not catered for properly in the code. The manual is misleading in that respect, true EP brake systems are not modelled.

Far as my parameters go, I use the standard air single/twin with a distributor and a three notch controller. Gives me EP behaviour which is what we are looking for.

[coolhand101]

Nothing confusing about it. EP is exactly the same as a normal self lapping brake system with the exception of electric control. Electric control however is not modelled in ORTS far as I can see. No brake system can operate without having pipes defined in the eng file whether it be vacuum, air or EP. I do not see it as a fault or bug, just something that is not catered for properly in the code. The manual is misleading in that respect, true EP brake systems are not modelled.

Far as my parameters go, I use the standard air single/twin with a distributor and a three notch controller. Gives me EP behaviour which is what we are looking for.

Confusing as them brake tokens do not exist.

Also i think your taking about the westcode 3 step brake? I'm talking about the E.P/Westinghouse brake(auto)

Most 3rd generation EMU/DMUs in the UK have, Release, Step 1, 2 ,3 and Emergency. The air is taken from the Main reservoir, there is no brake pipe on these units.

In OR, the 5 position E.P/AUTO brake function of my 2nd Gen EMU,is almost modelled correctly. ie

1.Release
2.Full EP
3.Lap
4.Service
5.Emergency

Between position 1 and 2, the E.P brake in applying is self-lapping, the brake pipe does not move, and air is taken from main reservoir(drop in pressure)

Between position 3 and 4, the Auto brake is manual, the brake pipe drops, the main reservoir holds.

If the EP brake token in OR had graduated release, this setup would be almost prototypical.

Thanks

[baldwin]

Also i think your taking about the westcode 3 step brake? I'm talking about the E.P/Westinghouse brake(auto)

Most 3rd generation EMU/DMUs in the UK have, Release, Step 1, 2 ,3 and Emergency. The air is taken from the Main reservoir, there is no brake pipe on these units.

First of all, as you know, there is more than one form of EP brake. Only one is coded in OR, twin pipe with triple valve. No EP brake system can work without at least one pipe to carry the air from the main res to each car in the train. Far as I am aware, the main res is not used on later units with the train pipe replacing it as the main res.

On your system you should have EP_single_pipe which is basically the standard air_single_pipe with the triple valve replaced by distributor. Until you have a pipe in the system, lapping is not going to happen.

It is not a bug, just what you are trying to do does not fit OR code. It should be possible at some point to code for the different varieties of EP brakes though.