Paul3 gdelmoro,At my club layout, we run freights at two speeds: drag freights (coal, ore, etc.) run at 25mph while merchandise freights (everything else) run at 45mph. Meanwhile, commuter passenger trains run at 65mph while regular passenger trains run at 79mph. All these trains are timetable/scheduled runs and we use a 6:1 fast clock. I know it sounds involved, but then our layout is bigger than most. From end to end, the mainline is about 600 feet long. Even at 60mph, it takes 10 minutes to run the whole main. The different train speeds makes dispatching much more interesting, however. That equals fun...at least to me. For a bedroom-sized home layout, that's pretty much out of the question. When I had a small layout, a slow run made it seem longer.
gdelmoro,At my club layout, we run freights at two speeds: drag freights (coal, ore, etc.) run at 25mph while merchandise freights (everything else) run at 45mph. Meanwhile, commuter passenger trains run at 65mph while regular passenger trains run at 79mph. All these trains are timetable/scheduled runs and we use a 6:1 fast clock.
I know it sounds involved, but then our layout is bigger than most. From end to end, the mainline is about 600 feet long. Even at 60mph, it takes 10 minutes to run the whole main. The different train speeds makes dispatching much more interesting, however. That equals fun...at least to me.
For a bedroom-sized home layout, that's pretty much out of the question. When I had a small layout, a slow run made it seem longer.
On my MUCH smaller layout mainline loop about 45' and curves are 28 & 30 with some 26 that 79 mph commuter would look really strange. Your layout must be really nice and fun to run.
Mine simulates a branch line in teh 1950 - 60 era. It's hauling lumber, food and various products for the adjacent city. I sometimes have one train following another on the same line so at 79 mph it would be more like the Adams Family than an operation.
Gary
maxman 7j43k I DID have to change some CV's to get to use the custom speed table. I just did what the directions said: Change CV 29 to 1 and change CV 25 to 16. As I recall. You also said that you set CV 29 to 1. Looking at the table on page 20 of the instructions you linked this indicates that you are not using a speed table, 14 speed steps, and the direction is reversed from normal. Oh, and a short address. So the value in CV 25 would not matter. I don't think you really set CV 29 to a value of 1. On the other hand, if it was CV 29 in which you put in a value of 16, then you would be having a speed table, normal direction, still a short address, and still 14 speed steps. You would have still needed to do something with CV 25. If you really have the speed table enabled, then changing the value of CV 67 from the default value of 9 to a lower value would decrease the starting voltage to the loco, hopefully allowing it to run at a slower speed.
7j43k I DID have to change some CV's to get to use the custom speed table. I just did what the directions said: Change CV 29 to 1 and change CV 25 to 16. As I recall.
You also said that you set CV 29 to 1. Looking at the table on page 20 of the instructions you linked this indicates that you are not using a speed table, 14 speed steps, and the direction is reversed from normal. Oh, and a short address. So the value in CV 25 would not matter.
I don't think you really set CV 29 to a value of 1.
On the other hand, if it was CV 29 in which you put in a value of 16, then you would be having a speed table, normal direction, still a short address, and still 14 speed steps. You would have still needed to do something with CV 25.
If you really have the speed table enabled, then changing the value of CV 67 from the default value of 9 to a lower value would decrease the starting voltage to the loco, hopefully allowing it to run at a slower speed.
This emphasizes my point about double checking what I said.
The directions say:
"Set bit 4 (STE) of CV 29 to 1 to enable speed tables.
Enter a value of 16 into CV 25 to enable the 28-point custom speed table."
So, yes, it does look like I did not set CV to 1, since the changes did what I expected. I must have done the above quoted actions. Because it worked.
Ed
7j43kI DID have to change some CV's to get to use the custom speed table. I just did what the directions said: Change CV 29 to 1 and change CV 25 to 16. As I recall.
rrinker Not sure where you get that CV67 would be 9 for the default, nothing set, straight line speed table. CV67 by default is 0, it's CV68, step 2, that is 9.
Not sure where you get that CV67 would be 9 for the default, nothing set, straight line speed table. CV67 by default is 0, it's CV68, step 2, that is 9.
page 26 of the User's Guide:
http://www.soundtraxx.com/manuals/tsu2_diesel_usersguide.pdf
where the table (first row) shows CV 67 and a value of 9
And, as I said, at speed step 1 of 128, it did not crawl. That is why I was inspired to change to speed table to something more acceptable.
However, with no speed table in effect, on step 1 out of 128 the loco shoould barely crawl. Tsunamis have BEMF so it should move. Each step with 128 steps is almost imperceptible, it takes 4-5 steps before you really notice the difference in speed (not coincidently about what a difference of 1 step is in 28 step mode). A 2 or 3 in CV3 for a tiny bit of momentum smooths everything out without causing a big delay in response - in fact some decoders have a default of 1, not 0 for momentum. This does not affect slowing or stopping the loco, that would be CV4. Maybe with that new Iowa Scaled Engineering prototypical throttle I'd try a large momentum for decelration as well, since it has a proper brake, but flipping a function on and off for the brake and trying to stop a train precisely when using high momentum just doesn't cut it. Acceleration is a completely different story. Not that it applies to a motor car, unless it has an automatic transmission.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinker If this is exactly what you did, then wow, Tsunamis are VERY strange. Or you had a non-zero value in CV2. Because is CV2 was set to 0, then WITHOUT a speed table it's already starting as slow as it can start on step 1. Changing over to a speed table and making step 1 = 1 is EXACTLY the same thing as stock with no speed table, it should not make it run slower. It just does not make sense that setting step 1 of a GREATER change per step to 1 results in a SLOWER start than a much smaller change per step.
If this is exactly what you did, then wow, Tsunamis are VERY strange. Or you had a non-zero value in CV2. Because is CV2 was set to 0, then WITHOUT a speed table it's already starting as slow as it can start on step 1. Changing over to a speed table and making step 1 = 1 is EXACTLY the same thing as stock with no speed table, it should not make it run slower. It just does not make sense that setting step 1 of a GREATER change per step to 1 results in a SLOWER start than a much smaller change per step.
If the decoder was delivered with a linear speed "curve" (straight line from zero to full), then speed step 1 (of 28) would have had CV 67 set to 9. I changed it to 1. That is certainly not the same. And I continued.
I did not read the existing CV's, as I had a "keep-alive" installed and had to program on the main.
Anyway, what I did was a dramatic change. It was exactly what I wanted, first time out.
I DID have to change some CV's to get to use the custom speed table. I just did what the directions said: Change CV 29 to 1 and change CV 25 to 16. As I recall.
CAUTION: Do NOT just believe me if you want to do this, too. Double check for yourself. But I used the directions and it worked. So I must have been darn close. Or correct.
I didn't want momentum. Particularly. It might have worked; can't say it wouldn't.
I did read about the 3 CV approach, but I liked the elegance of building the whole curve. After all, with 3 CV's, it ain't a curve; it's a corner.
And, yes, 28's more work than 3.
I did notice somewhere some pre-made curves that are similar to what I built, but I didn't see them until I was already done. And now I can't find them.
What I particularly wanted to point out is that the system builds the 128 speed steps out of whatever it has in the 28 speed step specs. You're just turning on a sort of "extrapolator".
I suspect one of two things, either CV2 wasn't 0, so the starting speed was set to something well above the slowest, or you weren't actually starting at an indicated step 1 on the throttle. Most likely the former.
The speed table you went through the effort to create can be effectively replicated by putting something other than 0 in CV3 to give a little momentum. The loco would only gradually speed up even if you went from 0 to step 10 on the throttle instantly. And/or set CV5 for max speed such that at full throttle it won;t go warp speed. Of course the change would be linear from 0 to full, but now instead of say 0 to 60 smph, it now is only a range of 0 to 30 smph. Yet there are still the same number of throttle steps in between - each one is now only half the amound of change as before. To get a non-linear response you need a decoder with CV6 support, or else the full 28 step tables. I know which one I prefer.. 3 CVs to set vs 28.
I put a Tsunami 2 in my gas-electric. Using the stock speeds, it stepped out a little too quickly on speed step 1 (of 128) for my tastes.
I thought I'd try making a custom speed table, per the directions.
I decided I wanted a very slow increase in speed while starting out, but when I got towards top speed, I wanted it to change quickly.
There are 28 speed step entries to make. For each entry, you enter a number from 1 to 255. Those latter numbers represent the nominal output voltage to the motor. You can see that there are pretty fine divisions, there.
Because gas-electrics are kind of slow pokes, I decided to enter 1 for speed step one. Then 2 for step 2, and on up. Well, if that continued the same way, I'd only be at 28 (instead of top speed--255) at step 28. So I started introducing bigger changes as I went up from the low numbers to 28.
I will here note that the 128 speed step systems uses the same numbers as the 28 speed step system. It just interpolates to get its 128 steps.
Anyway, I put the little guy on the track (NCE Power Pro). A REMARKABLE improvement. I had all this slow speed control--so many choices. I had thought that it perhaps wouldn't even go at step 1 of 128. After all, I had put in 1 for the lowest number. So 1 of 128 is sorta like .2, really. Anyway, it runs at 1.
That's the first time I've messed with the custom speed table, and I love it. I've got three Athearn RS-3's that are sweet runners, but also need better low speed control. I'm going to put the same or similar speed curves in those, when I have the time. It DOES take awhile.
Thanks for the posts. I think I'll keep them running slow.
Randy, thanks for the suggestion. I think I'll watch Dana's DCC video and then give the 128 a go.
This is a project I have for when I get a working layout again, setting all my locos to run reasonable speeds. Another reason I won't use Tsunamis, I want to set all this using just CV2, 6, and 5. Top speed will be set to something plausible for the type and use of a particular loco, but all locos of the same class will have the same speeds set. Mid point will be set based on use of the loco. Speedy passenger locos will have a higher CV6 setting so they get up to speed quicker, freight locos will have a lower CV6 so they take longer to reach track speed. CV2 will be adjusted as needed to get the loco to start and run reliably as slow as it can be made to go.
I use 128 speed steps always, since that's what Digitrax defaults to. NCE defaults to 28 but can do 128 - give 128 a try. If you read any of the reviews of DCC locos in MR, they will usually list a minimum starting speed at 28 steps and then a lower one when using 128 steps. They don;t usually put that int he table at the end of the review, but Dana usually mentions it in the text of the review. 128 gives a much finer control and close enough to a DC analog potentiometer as to not matter. 28 steps divides (let's make it easy and say 14V to the rails) 14 volts into 28 steps of half a volt each - especially on more modern models, half a volt is quite a jump in speed. Yes I am simplifying here for the explanation. Yes, you can level this out by putting some non-zero momentum. But give 128 steps a try. The throttle wheel has ballastic tracking so if you really need to jack rabbit start, or stop quickly, you can roll it faster and instead of 1 step per click you can get many, if need be.
At home and at the club I find myself running trains slow, to me it looks better, feels better, and most get more enjoyment out of running trains slower regardless of scale MPH. Just looks better.
I was at a Free-mo setup a few weeks ago.
There were about 15 people running trains. I would say everyone, when out on the main and having green blocks, ran their trains slower than prototype speeds. I know I did. I wanted to watch and enjoy my trains running. The longer, the better.
Gary,
Obviously it would depend on the area and speed of the mainline in that area. NYC freight could go lickity-split (50+MPH) out on the long, straight stretches in rural-like areas. More urban and congested areas would see more reduced speeds.
I think the "compression" of an average layout also adds to the illusion that trains are traveling at higher "scale" speeds than they actually are.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
the Norfolk southern Weekley Performance Report lists average train speeds for various types. Looks like the range for freight is beween 15 and 30 mph.
greg - Philadelphia & Reading / Reading
So I'm running my trains at speed step 14 and they look good at that speed. When I calculated the MPH it was only 20MPH. I thought that most mainline freights do 40. When I try to go 40 it looks ridiculous.
What speed do you guys run freights on Mainlines?