Smokebox Consolidation-Brake Issue

[engineerbj]

Hello All,

I'm having a little issue with the ATN Consolidation from Smokebox. I recently applied the latest update from here on RWA, and I've run into a bit of a problem. Whenever I switch from the Consolidation to another engine, say to move the other engine out of the way, then go back to the Consolidation, the brakes keep going into emergency and I can't for the life of me get them to release properly, even with both the independent brake and the train brake set all the way over to the left in "release" territory.

What's worse, even if I do somehow manage to get them released, they slam back into emergency as soon as I start to move the engine again, and the brake handles keep fighting every move I make to release them, so I am just doing something wrong, or is this a glitch of some kind?

Any assistance would be greatly appreciated,
Brendan O.

[tomgiorgini]

I HAD A BRAKE HANGING PROBLEM WHICH WAS RELATED TO THE NEW UPDATES.NOT HAVING THE DOCUMENTATION.WAS READING THE POSTS IN THE CONSOLIDATION THREAD IN DTG WIP SECTION.YOU HAVE TO LEAVE THE TRAIN BRAKE HANDEL IN RUN NOT FULL RELEASE OR IT WILL OVERCHARGE THE LINE.WHAT I WAS DOING WAS KEPT HITTING RELEASE AND THE BLACK HAND ON THE BRAKE GAUGE WOULD JUMP UP TO THE 120 PSI WHICH I GUESS WAS CAUSING THE BRAKES TO HANG ONCE I KEPT IT IN RUN THE LOCO RAN GREAT MIKE IS UPDATING THE MANUEL SO WE HAVE THE PROPER INFO.I DONT KNOW IF ANY OF THIS WILL HELP YOUR SITUATION.MIKE SHOULD SEE THIS AND COMMENT I WOULD THINK.CHECK OUT THE OTHER THREAD ON THE LAST FEW PAGES AND PERHAPS LEAVE YOU POST THERE sorry for shouting didnt realize the caps lock was on

[mrennie]

Yep, it's what Tom said - if you put the automatic train brake in Release for too long, it overcharges the brake pipe. Here's what the new manual says (yeah, I forgot to put the new manual in the package):

The train brake handle has some additional scripting to simulate the tactile feeling of moving the handle in and out of the indents in the brake quadrant, which helps to avoid accidentally moving the handle by more than you intended. The complete set of indents that are "protected" (checked by the script to prevent unintended movement) in this fashion are as follows:

o RUNNING at 34% ‐ the indent is checked when going towards either RELEASE or HOLD.

o HOLD at 42% ‐ the indent is checked when going towards either RUNNING or SERVICE (ignoring LAP on the way to SERVICE).

o LAP at 62% ‐ the indent is checked when going towards HOLD.

o SERVICE (or APPLICATION) at 74% ‐ the indent is checked when going past it towards either EMERGENCY or LAP.

If the train brake handle seems to get stuck as you move it, it is because it has hit one of those indents (you'll also hear a soft "click"). When that happens, stop moving it, wait at least half a second, and then continue to move the handle.

For example, when the handle is moved to the right from RUNNING to SERVICE, it cannot go farther until the player has stopped trying to move it for at least half a second. After that time, the handle can be moved all the way to EMERGENCY.

If the handle is moved with the mouse, it's not necessary to release the mouse button, but just stop dragging the mouse to the right for one second.

• In the "Advanced" version, the various positions of the automatic brake handle perform as follows (listed here in order from right to left on the brake quadrant):

RELEASE connects the brake pipe directly to the main reservoir but holds the locomotive brakes, if set, applied (the brake cylinder pressure shown in the cab gauge stays steady).

RELEASE should not be used in normal operations, because if left in this position,the brake pipe can become overcharged to more than the 90psi setting of the feed valve. It should really be used only to recharge an empty brake pipe, on a long consist, when the brake difficulty is set to "Hard".

If RELEASE is used, the handle should be moved to RUNNING before the brake pipepressure gets close to 90psi.

o RUNNING, on the other hand, releases the locomotive brakes as well as the train brakes. In this position, the equalizing reservoir and brake pipe are charged up to 90psi. This is the normal position for recharging and releasing all brakes, and when running (in order to maintain the brake pipe at 90psi).

o HOLD releases the train brakes (the equalizing reservoir pressure rises to 90psi, with the brake pipe pressure following it), but holds locomotive brakes, if set, applied.

o LAP, when reached from SERVICE, stops the equalizing reservoir pressure from reducing, keeping it steady at the current pressure.

o SERVICE (or APPLICATION) reduces the pressure in the equalizing reservoir ‐ it continues to reduce for as long as you keep the handle in this position. The drop in equalizing reservoir pressure is followed more slowly by the brake pipe pressure (remember that the black hand on the left‐hand brake gauge shows the pressure at the head end of the brake pipe) as the air in the brake pipe (or "train line") vents through the "small hole" in the locomotive's brake stand. The two pressures (brake pipe and equalizing reservoir) eventually equalize but the time it takes for that to happen depends on the length of the consist.

o EMERGENCY gives a rapid reduction of brake pipe pressure and an emergency application of the brakes. You have to wait for the brake pipe pressure to drop to zero before being able to release the brakes.


Pressure equalization

The brake pipe pressure equalizes first at the head end of the train (that is, at the end of the brake pipe that goes into the equalizing reservoir in the locomotive), taking longer to equalize at the rear end of the train. This means that the train brakes don't apply on every car in the consist at the same time. Instead, it takes longer for them to apply the farther they are from the head end.

Even if the gauge in the cab is showing that the brake pipe pressure has equalized at the desired reduction, the full braking effect won't be felt until the reduction has reached the tail end. The time for that to happen depends on the length of the consist and this is something that you need to take into account when planning your brake applications.

Note: there is no gauge in the cab that shows the brake pipe pressure at the tail end of the train, but if you look at the F5 HUD, the "Brake Cylinder Pressure" shows the average pressure in the cars' brake cylinders. Therefore, when that pressure reaches a steady value, it's an indication that the tail end brake pipe pressure has equalized.

As the brake pipe pressure reduces, the engine brake cylinder pressure will rise by a corresponding amount, at a ratio of 1:2.5. For example, a 10psi reduction in brake pipe pressure results in a 25psi increase in engine brake cylinder pressure.

The engine brake cylinder pressure cannot rise above 65psi.

The normal pressure for the fully charged brake pipe and equalizing reservoir is 90psi. When a reduction is made, the first 6psi reduction in brake pressure (called an "initial reduction") triggers the "quick service" feature of the brake valves on the cars in the consist. Then, instead of the brake pipe air having to travel all the way to the "small hole" in the locomotive brake stand, it vents at the cars themselves, very quickly. In that way, it's possible to get 15psi (2.5 times 6psi) into the cars' brake cylinders very quickly. After the initial reduction, further reductions happen at the normal rate (that is, more slowly) as the air has to travel all the way up the brake pipe to the locomotive.

Train brake triple valves and auxiliary reservoirs

Every car in the consist is equipped with an auxiliary reservoir that holds the air used by the brakes in the car, as well as a triple valve that controls three main operations of the brakes:

• recharging the auxiliary reservoir with air taken from a branch pipe connected to the main brake pipe (or "train line")
• venting the air accumulated in the car's brake cylinders, so that the brake cylinder pressure falls to zero and the car's brakes release
• charging the car's brake cylinders with air from the auxiliary reservoir, so that the car's brakes apply

As soon as the pressure in the branch pipe is higher than the pressure in the auxiliary reservoir, by at least 1.5psi, the brake cylinders vent all the air to atmosphere, releasing the brakes, and the auxiliary reservoir begins to recharge (the pressure in the reservoir increases).

There is no partial release (brake cylinder retainers are not simulated) and the air is vented very quickly.

Brakes don't release on all of the cars in the consist simultaneously. It takes time for the brake pipe pressure wave to travel down the brake pipe to each car. The brakes release first at the head end, closest to the locomotive, and lastly on the car at the rear end of the train. The "Brake Cylinder Pressure" in the F5 HUD is the average pressure in the brake cylinders of all cars in the consist, and that average pressure determines the actual braking effort applied to the train by the simulation.

Therefore, if you watch the F5 HUD while releasing the brakes, "Brake Cylinder Pressure" will not change until the brake pipe pressure has risen by 1.5psi. Then, "Brake Cylinder Pressure" will rapidly drop to 0psi, without stopping even if you move the handle to SERVICE, while the brake pipe pressure (shown by the gauge in the cab) continues to rise (at a rate that depends on the length of the consist).

Overcharged brake pipe

RELEASE connects the brake pipe directly to the main reservoir, circumventing the feed valve. Thus, the brake pipe pressure can continue to rise above 90psi.

The brake pipe, in turn, recharges the auxiliary reservoirs in the cars, albeit much more slowly (this is because the auxiliary reservoirs recharge off a branch pipe, coming from the main train line, via a narrow feed groove in the triple valves which limits the rate of flow of the air into the reservoir).

If the handle is left in this position for too long, the brake pipe pressure and the auxiliary reservoirs can be charged to more than 90psi.

When the handle is returned to RUNNING, the brake pipe gradually leaks back down to 90psi.

However, if the auxiliary reservoirs are also charged at more than 90psi, that leakage is detected by the cars' triple valves as a reduction, which produces an unintended brake application. The train brakes are, therefore, applied (partially) but the brake pipe is still at its nominal maximum of 90psi, with the automatic brake handle already in RUNNING, so the brakes cannot be released (brakes are released by raising the pressure in the brake pipe, but in RUNNING, the brake pipe pressure cannot be increased above 90psi). You can still bail off the engine brakes, but the train brakes are stuck on!

In this condition, if you move the automatic brake handle to RELEASE, the train brakes can be released, but as soon as you move it back to RUNNING, they apply again.

The method for recovering from an overcharged brake pipe is as follows:

• Make an emergency application of the train brakes (move the handle to EMERGENCY)
• Wait for the brake pipe pressure to fall to 0psi
• Move the handle to RUNNING in order to recharge the equalizing reservoir and brake pipe to 90psi.

There's a lot more in the manual, but that snippet I've given you should help you see how to use the brakes.

[engineerbj]

Ah, I get it now. I'm used to leaving the thing in "Release" because that's where you keep it in real life when running to overcome any tiny leaks in the train pipe or in the flexible connections between cars (no seal is perfect). However, in this instance, the "Release" position in the sim is more like the "Quick Release" position on some of the old brake stands (can't remember the exact model, but the SP 2472's got ones that work just like this,) and "Running" is the equivalent to the normal "Release" position.

So if I accidentally overcharge the pipe, like I've apparently been doing, I have to "big hole 'em" to flush all the air out and then recharge in the "Running" position to unstick the brakes and re-set the system. Got it, I'll give it a try and see how things go.

Thanks guys, it's much appreciated!

Brendan O.