Loss of steam pressure in idle locomotives

[prdarby]

Driving British (mostly Great Western) steam locos in Cab mode, I find that if I go to a loco that has been standing idle for a while - maybe I've switched engines after an hour or so of gameplay - I can get the water, coal and boiler pressure just where I want them, but as soon as I start moving, the boiler pressure immediately drops right down to zero. Is there something else I need to do to prevent this? I'm guessing that there's cold water or condensation somewhere in the system away from the boiler, but can't figure out a way of dealing with it.

This happens if I take an engine that's been waiting on shed for a while, or if I take over one that's been running on AI.

Any insight gratefully received!

Cheers, Paul

 

[captainkman]

Hi there,

To see if the engine you're driving (or taking over) is going to drop pressure when moved, open the firebox and look at the fire. If it is not too bright (i.e. a red or yellow colour) the engine will most likely drop boiler pressure when you move it.

To avoid this, open the blower until the fire starts turning nearly white. Then it is safe to turn it off and start to move the engine.

I don't know if this is how a real steam engine is driven, but it works for Trainz steam engines.

Kieran.

 

[prdarby]

That's what I expect it to do in theory, but it's not what I'm finding happens. Bit more detail - let's say I'm running a session with 2 main locos. I've got a small shunter to put a train together, and a larger engine to haul it. It takes maybe 25 minutes to assemble the train, then I go to the larger engine and prepare to bring it to the head of the train. Typically when you go straight to an engine like this you'll find about 70% coal, 35% water, cold looking fire, mid-range pressure. So, I top up the coal, open the blowers to get some heat into it, and maybe add some water. In most cases, at this point, especially with smaller engines, the pressure now starts to drop away instead of rising. Is there anything else I need to do? Am I simply adding too much coal and water too fast, or is there something else I'm missing? I notice that most engine cabs have working water drains, but I can't find anywhere what they're for or what effect they have.

 

[captainkman]

Hi Paul,

I believe it's the act of adding coal and water that causes the drop in pressure. Adding coal to a warm fire usually cools it down (in the Trainz world, at least). Try getting the temperature back up with the blower, then try replenishing the coal and water and/or moving the locomotive.

The water drains, while they may be functional cab levers, aren't actually connected to the physics system in any way.

Another thought occorred to me, and that is that this may very well just be a TS12 bug. Some confirmation or denial of this would be quite handy. While I have TS12, it isn't installed, so I am unable to check.

Kieran.

 

[Bill69]

That's what I expect it to do in theory, but it's not what I'm finding happens. Bit more detail - let's say I'm running a session with 2 main locos. I've got a small shunter to put a train together, and a larger engine to haul it. It takes maybe 25 minutes to assemble the train, then I go to the larger engine and prepare to bring it to the head of the train. Typically when you go straight to an engine like this you'll find about 70% coal, 35% water, cold looking fire, mid-range pressure. So, I top up the coal, open the blowers to get some heat into it, and maybe add some water. In most cases, at this point, especially with smaller engines, the pressure now starts to drop away instead of rising. Is there anything else I need to do? Am I simply adding too much coal and water too fast, or is there something else I'm missing? I notice that most engine cabs have working water drains, but I can't find anywhere what they're for or what effect they have.

This is mostly to do with the engine spec. If the min-fire-temperature is set too low you will run out of steam eventually. Also when using the blower do not open it fully, just crack it a couple of notches and have some patience. Let me know what loco this is happening to and I will have a look at it.

Cheers,
Bill69

 

[S301]

A couple more points here, you've got a lot of volume in most boilers! It's going to take time for a hot fire to make the water hot.

My suggestion would be to do a few things with steamers in this situation. First would be to place the loco in a 'shed' road... Then, go back to the loco about 5-10 minutes before you need it and put some coal in (and water if it's below about 60-70%), and crack the blower a little (press N once IMO). At the same time, move the loco from the shed road, to a 'train ready' point (e.g. if there's a turntable, move to the turntable, turn if necessary, then out to, say, a water column to top up the tender). This will drop the boiler pressure, but you should now get a realistic indication of how the loco is going. If needed, open the blower a little more (depends on how low the pressure is). Now finish your shunting (put it down to the shunter having to wait for another train - You could always have an AI train setup to 'cause' the stop in shunting ), and then when you're ready, go back to the larger loco.

Note, it's generally good practice to be 'close' to full pressure, but not too hot, when you bring a loco onto the train. Then, whilst you do the brake test and wait for departure, you make it truly hot. You'll generally have a good 5-15min at a minimum wait at a station, at least that's what I've seen in Aus, plenty of time to go from '90%' to '99%' pressure. When you're making pressure, you know you've got a reasonably hot fire.

If you're using TS12 SP1, and you're running a passenger service, I'd recommend putting the rule 'Advanced Industry Load Configuration' and setting up at least the first station. Untick the option for 'Lock Train Controls during Loading', that way you can keep warming it up (and putting in water if needed) right up till departure, whilst still loading passengers. You might also want to put it in for other stations as well That way you can prevent blowing off as much as possible!

Zec

 

[Trackman53]

I noted that this is happening so I setup a session that has over 50 different steam loco's including the N3V NKP and everyone of them after standing for 1 hour has over filled the firebox. This seems to smother the fire and the engine will not begin making additional steam until the coal "level" is under 100%. Setting the blower to high or some setting in between didn't help either.

You can see this by moving the engine 1/2 mile. As the engine begins to move the steam boiler pressure drops until the engine stalls.

The engines varied between 112% to 138%. Some the blowers default in the on setting and some do not. Didn't seem to make any difference.

The question is what in the engine spec's is causing the coal level to exceed the 100% level when standing?

 

[Azervich]

starting-coal

that tag should be bellow ideal-coal tag.

Cheers.

 

[Trackman53]

On almost all the steam loco's the starting coal level shown in game is 100% at the beginning of the session.

ITs after the session has run for an hour or more than the level exceeds 100%. This seems only to apply to a loco than is idle. If the focus is on a loco then that loco will/may not have the problem of coal level exceeding 100%. In other words some do and some don't, but only if it is in the focus (active) loco. Otherwise the above applies.

 

[Azervich]

That's rather interesting.... when left idle the coal slowly burns away, only thing I can think of is the locos in question are using a TRS2004/2006 coal shovel script as that keeps shoveling until the pressure is high, that no longer works in TS2009+.. it keeps shoveling until the firebox is full.

Cheers.

 

[Trackman53]

Nope several of these loco's including the NKP will not work in other versions or were "written" for TS12 only.

None of the ones I have that are having this issue have the fireman script. One of the ones that is over filling the firebox has no tender attached. Some are from bdaneal (Loco Baldwin heavy 4-4-0 TS12). All the ones I am testing with, over 50 different steam loco's" have this issue.

 

[Trackman53]

So I put in a help desk ticket, and N3V has confirmed that this happens.

Quote:
You may be able to work around this issue by adjusting either the 'shovel-coal-mass' or the 'burn-rate-idle' tags, since it appears that Trainz is shoveling coal in to some degree when idle, but is not burning it off as quickly as it is shoveled in. Please keep in mind that adjusting the burn-rate-idle tag will change how hot the boiler is when idle, whilst changing the 'shovel-coal-mass' will simply reduce the amount of coal fed in for each shovel (both manually, and via the coal slider).
Unquote.

So what change could be made that would help?

 

[Ben1337]

Sorry about bumping an old thread, but How do I burn off the excess coal / drop the fire?