class 37 brakes

[AndyUK]

Class 166s have three step Westcode brake control.

Does anyone have the brake pipe pressure at each step please? I'm going to try to give the power / brake handle some "notches" in the braking area and want to get the pressures set up accordingly.

Although I'll be doing it in RailSim I assume that my work won't be wasted if I switch to RailWorks as presumably that's not one of the things that RS.com got around to fixing?

Andy L

[davveb]

Andy

There is no brake pipe in a Westcode installation, as it is a pure electro-pneumatic system. An electric wire performs the role of the brake pipe. A main reservoir air pipe provides air at constant pressure to keep each units brake reservoir constantly topped up. This is maintained at about 7bar and the pressure is shown on the left hand needle in the cab. The right hand needle indicates the brake cylinder pressure in the driving unit. It should be the same in all units. On UK EMU/DMUs of 80s early 90s vintage each "step" of braking increases the pressure by at least 1bar. I.e step 1 is 1bar, step 2 2bar and full service (amusingly marked "fuel service" if you look closely at the cab graphics) is 3bar. For trains without "enhanced emergency braking" the emergency step gives the same application pressure as full service.
However, on the real trains the brake force for each step is not constant as there is a clever interaction with the air suspension. The air suspension pressure is varied to maintain a constant floor height with varying train weight, i.e the more load the more the pressure is increased. This is linked to the brakes to provide higher brake cylinder pressure for each step when the train is heavier. As there is no simulation of varying train weight with varying passenger loads in Railsim then there's not much point in trying to simulate this.

Dave B

ps
There are "issues" trying to setup variable step notches with the "combined controller" type used in the class 166. You'll need to use LUA scripting techniques to get around these. I did an update to the 166 a while back, but never got arround to posting it here. There were a couple of things I was planning on improving, but I could put it up if people are interested.

[AndyUK]

Andy

There is no brake pipe in a Westcode installation, as it is a pure electro-pneumatic system. An electric wire performs the role of the brake pipe. A main reservoir air pipe provides air at constant pressure to keep each units brake reservoir constantly topped up. This is maintained at about 7bar and the pressure is shown on the left hand needle in the cab. The right hand needle indicates the brake cylinder pressure in the driving unit. It should be the same in all units. On UK EMU/DMUs of 80s early 90s vintage each "step" of braking increases the pressure by at least 1bar. I.e step 1 is 1bar, step 2 2bar and full service (amusingly marked "fuel service" if you look closely at the cab graphics) is 3bar. For trains without "enhanced emergency braking" the emergency step gives the same application pressure as full service.
However, on the real trains the brake force for each step is not constant as there is a clever interaction with the air suspension. The air suspension pressure is varied to maintain a constant floor height with varying train weight, i.e the more load the more the pressure is increased. This is linked to the brakes to provide higher brake cylinder pressure for each step when the train is heavier. As there is no simulation of varying train weight with varying passenger loads in Railsim then there's not much point in trying to simulate this.

Dave,

Thanks for the info ref the pressures. I lapsed into old money EPB speak when talking about the brake pipe, my defence is I've been up since 0400 but I did get excellent value for money from a £10 Southern Daysave!

ps
There are "issues" trying to setup variable step notches with the "combined controller" type used in the class 166. You'll need to use LUA scripting techniques to get around these. I did an update to the 166 a while back, but never got arround to posting it here. There were a couple of things I was planning on improving, but I could put it up if people are interested.

I'd be interested if you wouldn't mind posting your 166 update please. I've got your others and the Class 86 and that's what inspired me to have a go myself on the 166.

Andy L

[GavNormandale]

hi all, having just ran the hedborough north 'new arrival' scenario, i think this is where i have got it into my head that there is something wrong with the class 37 brakes, i think it may now be a problem with the bitumen wagons, the scenario begins by telling us that this is a heavy train and will take time to get moving, im sure this heavy train would take some stopping as well but on nearing the end of the scenario and i have to slow for speed limits and stop at the end, with minimal braking the train seems to slow as if it were a light engine!

has anyone else noticed this?

Gav

[JLChauvin]

Andy

There is no brake pipe in a Westcode installation, as it is a pure electro-pneumatic system. An electric wire performs the role of the brake pipe. A main reservoir air pipe provides air at constant pressure to keep each units brake reservoir constantly topped up. This is maintained at about 7bar and the pressure is shown on the left hand needle in the cab. The right hand needle indicates the brake cylinder pressure in the driving unit. It should be the same in all units. On UK EMU/DMUs of 80s early 90s vintage each "step" of braking increases the pressure by at least 1bar. I.e step 1 is 1bar, step 2 2bar and full service (amusingly marked "fuel service" if you look closely at the cab graphics) is 3bar. For trains without "enhanced emergency braking" the emergency step gives the same application pressure as full service.
However, on the real trains the brake force for each step is not constant as there is a clever interaction with the air suspension. The air suspension pressure is varied to maintain a constant floor height with varying train weight, i.e the more load the more the pressure is increased. This is linked to the brakes to provide higher brake cylinder pressure for each step when the train is heavier. As there is no simulation of varying train weight with varying passenger loads in Railsim then there's not much point in trying to simulate this.

Dave B

ps
There are "issues" trying to setup variable step notches with the "combined controller" type used in the class 166. You'll need to use LUA scripting techniques to get around these. I did an update to the 166 a while back, but never got arround to posting it here. There were a couple of things I was planning on improving, but I could put it up if people are interested.

Hello Dave,
Of course some of us are interested...
JLC

[davveb]

I've uploaded this 166 update. It's not ideal, the "lock" key behaviour can be a bit irritating if you use the mouse (caused by some strange side effect with the "rest in notched position" option). One thing I didn't model is the little red button on the end of the controller. I may not have a proper understanding of this (real drivers might want to correct me!) - but I think it acts a bit like a transmission engagement (i.e fluid filling) delay. When pulling away from rest press and hold the button, move the controller to say, notch 3, wait for the engine to rev up, then release the button and allow the transmission to engage. This could probably be simulated with a key and a virtual reverser definition.

Dave B

Edit - Just remembered this thread is in the RailWorks section. I don't have this sim version, so haven't tested this update in it. From posts others have made about using my other updates in RailWorks I don't see any reason why it shouldn't work, but please don't grumble if it doesn't, as there's nothing I can do about it at the moment.

[AndiS]

hi all, having just ran the hedborough north 'new arrival' scenario, i think this is where i have got it into my head that there is something wrong with the class 37 brakes, i think it may now be a problem with the bitumen wagons, the scenario begins by telling us that this is a heavy train and will take time to get moving, im sure this heavy train would take some stopping as well but on nearing the end of the scenario and i have to slow for speed limits and stop at the end, with minimal braking the train seems to slow as if it were a light engine!

Not that I own RW, but I would first check the Mass in the .bin file of the bitumen wagons.
Changes are that the figure they put there is compromise because they did not want to create two versions for (fully) loaded and empty. However, if you run a long train, you do notice the difference between empty and loaded.

Remedy would be to have two versions of the wagon, not to play with the engine brake, of course. Just a thought, driven by bad memories about MSTS.

[AndyUK]

One thing I didn't model is the little red button on the end of the controller. I may not have a proper understanding of this (real drivers might want to correct me!) - but I think it acts a bit like a transmission engagement (i.e fluid filling) delay. When pulling away from rest press and hold the button, move the controller to say, notch 3, wait for the engine to rev up, then release the button and allow the transmission to engage.

Dave,

Thanks for the upload, I'll give it a try.

Not sure about the 166 but having watched a video of an Electrostar, with a similar combined power / brake control, the red button seems to be used for "hill starts". It appears to hold the brake partially applied whilst the power electronics get themselves sorted out and deliver some tractive effort. It's just an observation not hard fact, but without such a device I can't see any other way of preventing the train from rolling back before moving the controller into the power range, thus releasing the brakes, has some effect.

Andy L

[phill70]

I know nothing about 166's, but I would say that red button, puts 10psi, or whatever the bar equivalent is, as Andy says for hill starts.
Most if not all Brush built locos had the same feature, but not for hill starts, it was more of an anti-wheelslip device.

[bigdaveadams1]

The red button/hill start button on most CPBCs holds 1.1 Bar of Pressure in the Brake Cylinders. On our 332s it holds
1 Bar but that's because the Germans like to be different.

As for westcode Braking I was lead to believe it was 1.1 bar for brake step 1, 2.2 bar brake step 2, 3.3 bar brake step 3
and Enhanced Emergency Braking was 3.9/4 Bar.

[AndyUK]

Thanks for the clarification. It's always good to have an input from someone with first hand knowledge.

Andy L

[davveb]

The red button/hill start button on most CPBCs holds 1.1 Bar of Pressure in the Brake Cylinders. On our 332s it holds
1 Bar but that's because the Germans like to be different.

As for westcode Braking I was lead to believe it was 1.1 bar for brake step 1, 2.2 bar brake step 2, 3.3 bar brake step 3
and Enhanced Emergency Braking was 3.9/4 Bar.

Thanks for that info. I might be able to simulate this hill start button function, but it will need yet another key. The Westcode pressures you quote are I think the ones I used in the simulation, so must have guessed right for this!

Dave B

[smarty2]

Yes i have noticed that the brakes seem more powerful than they ahould be. I dont know if it is me but i noticed a change in the braking performance after AP's soundpack install? But don't see how.

Mart

[irony39]

I have just bought railworks after using msts for a while and i find that stopping distances on railworks are really long compared to msts where most trains virtually stopped on a sixpence. Anyone else found this?

[PaulH2]

I have just bought railworks after using msts for a while and i find that stopping distances on railworks are really long compared to msts where most trains virtually stopped on a sixpence. Anyone else found this?

It is generally accepted that the brakes were much too powerful in many cases in MSTS. Driving a train is not like driving a car, even a short consist (or even light engine) will not stop on a sixpence. Most (including me) feel that, for the most part, the braking performance in RS / RW is much more realistic and you therefore have to drive accordingly.

Paul