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Not happy with Tsunami AT-1000 motor control. Any suggestions?

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Not happy with Tsunami AT-1000 motor control. Any suggestions?
Posted by hon30critter on Tuesday, March 19, 2013 11:27 PM

Hi everyone:

I have just installed a Tsunami AT-1000 in a Bachmann Spectrum Fairbanks Morse H16-44. This is my first Tsunami decoder. The decoder sounds good to me (I am absolutely not an expert on proper engine sounds) but the engine control is not acceptable. I am using an NCE Power Cab set on 128 speed steps.

My problem is that the locomotive is too quick off the start. After playing with the CV settings for quite some time the locomotive still starts moving too soon before the engine RPMs match the speed. To be exact, when I hit speed step 1 the engine rpms barely start to increase before the locomotive moves forward, and the forward movement is too fast. I have set the momentum to 9 and I have set CV 25 to 15 which supposedly lowers the start up voltage to the minimum.

I have read and reread all of the on line manuals. One of the things I can't seem to find is how to directly adjust start up voltage. I believe that what I need to do to correct the problem is simply reduce the start up voltage to the motor, but nowhere can I find a reference to the CVs which control that basic function.

FYI, I know that the decoder is receiving whatever commands I input because the loco jumps when I hit enter after setting the CV details.

So, I enlist your expertise!

By the way, I am not new to decoder installations. I have done about a dozen or more using various brands and I have been able to adjust the CVs in every one to suit my needs.

Thanks for your help.

Dave

So, I need your help

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by Jacktal on Wednesday, March 20, 2013 12:28 AM

With Tsunami decoders,CV2 controls the start voltage.However,using the speed table should do it too.Did you activate the speed table by setting CV29 bit 4 first.That might be your problem,the speed curve is useless unless you set CV29 first.

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Posted by tstage on Wednesday, March 20, 2013 12:45 AM

Dave,

Try adjusting CV212 (max BEMF) to 75 and see if that makes a different.  You can adjust down or up, as needed.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by rrinker on Wednesday, March 20, 2013 6:35 AM

 Now you see why the one Tsunami I have in a Bowser/Stewart FT is the only one I will ever buy.

Realistic sounds mean nothing if the operation is unrealistic.These are some top-notch smooth running locos, dead quiet and can easily creep tie to tie, so it's not the motor or the mechanism. It will run slow with the Tsunami, that's not a problem. But the moving before the motor revs is just plain wrong. On QSI and Loksound this is easy to fix, just add momentum. Turn the throttle slowly, the loco moves off with little prime mover revving, like a light engine move. Open the throttle faster, the prime mover revs and the loco moves off slowly, like it has a heavy train. Manual nothing on Tsunami can do this, but that seems to be a crutch. Speed matching Tsunami is much harder than it needs to be, also, since they do not support CV6 mid speed, so you are almost foreced to use a speed table.

That's why I standardized on ESU. Great sounds AND great motor control. I've said it before - if you remember the development story of Tsunami, when announced they were better than anything else on the market. However, they were delayed a considerable time from the announcement until release - in the time period the other manufacturers went through sometimes multiple revision upgrades, continually improving. The Tsunami has been left behind.

          --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by tstage on Wednesday, March 20, 2013 6:43 AM

rrinker

Realistic sounds mean nothing if the operation is unrealistic.

MRR-wise...Truer words have never been spoken.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by wjstix on Wednesday, March 20, 2013 9:00 AM

Tsunami decoders have superior operating ability IF you can set all the CVs correctly. You almost have to have Decoder Pro to get everything right. My Tsunami equipped Atlas RS-11 runs great, as does my Spectrum 2-10-0. Keep in mind the Bachmann H-16-66 is not as good an engine as an Atlas or Kato one, so isn't going to run as well as a more expensive engine regardless of the decoder.

If CV2 is zero, increasing it will only make the engine start quicker, not slower. Keep in mind your mid and top speed CVs (5 and 6) will affect how quickly the engine starts, as it affect the "straight line" speed curve. Try putting CV 5 at 100 and CV 6 at 50, with CV2 at zero and see how that works. If you need to delay the start more, increase CV 3 up to 20 or 30.

p.s. CV 25 controls which speed curve you use. I would set it back to a straight line curve, it may be the curve you're using does the opposite of what you want - deliver a lot of power right away. You also have to set CV 29 (IIRC) to allow using speed curves.

Jeff Otto (cover story, Model Railroad Planning 2013) wrote an article on programming the "Tsuper Tsunami" in the NMRA Twin Cities Division newsletter a few years ago that I found VERY helpful...

http://www.tcdnmra.org/cg-pdfs/Spring2007.pdf

Stix
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Posted by maxman on Wednesday, March 20, 2013 9:33 AM

wjstix
Try putting CV 5 at 100 and CV 6 at 50

Pretty hard to do if the decoder does not support CV 6.

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Posted by Train Modeler on Wednesday, March 20, 2013 10:04 AM

There are many CVs that address your issue.    BTW, sometimes locos can creep forward while idling.    Anyway, JMRI Decoder Pro makes what you're trying to do a whole lot easier.   I have even forgotten some of the CVs since that's how I tune the loco and sounds these days.    Get the correct decoder definition for your Tsunami which I believe is standard in the current version.    The current default for new Tsunamis are to go to notch 1(off idle) when when speed step 1 activated.   That used to not be the case and some have not tried the newer decoders so are unaware of this change.

Richard

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Posted by mlehman on Wednesday, March 20, 2013 10:08 AM

Maybe I'm just lucky or maybe it's because all mine are steam Tsunami's, but I've never had any big issues with motor control. Interestingly, while there isn't a CV 6 in the documentation, setting CV 6 is taken and acknowledged on the programming track. It does seem to have an effect, but since I stick to to a variety of mid-volt settings near the mid-range, maybe my eyes are fooling me about what effect it's having?Confused

BTW, TCS is bringing a sound decoder to market in the very near future that is between the Tsu and the Micro-Tsu in size, so there will be more competition heating up in this area of the DCC market. Several have mentioned the long in tooth status of the Tsunami and there is speculation that the timing is right for Soundtraxx to announce a next gen Tsunami, although I've heard nothing concrete on that.

Mike Lehman

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Posted by woodone on Wednesday, March 20, 2013 11:02 AM

Try working with CV's 209 and 210,  defaults are set at 25 and 20, set them lower. You have to have CV3 and 4 to set to zero before you set the CV 209 and 210.

I will post link to that here that has all kinds of infomation on the Tsunami's.

http://www.mrdccu.com/curriculum/soundtraxx/tsunami.htm

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Posted by selector on Wednesday, March 20, 2013 11:11 AM

I can no longer recall where I found this three years ago, but I used it on my BLI DC-version J Class 4-8-4 in which a friend installed a heavy steam Tsunami.  It is long and involved, but so are decoders in general, and their manuals even more.  However, I wanted something better from that J, and I got it.  If you want to see the magic resident in every Tsunami, go through this, ponder it, and then start fiddling with values.  My formerly jerky J now moves off like a real locomotive.

Try it...it works!

"

Tsunami PID/BEMF CV Tuning Concepts

I spent quite some time on the phone with Soundtraxx today. The following is a write up of what I was told. It includes knowledge I have gained recently in researching the PID process in general and the Tsunami decoders in particular. A PID controller is a well-known method of doing "process control". In our case the "process" is the speed of our Tsunami equipped locomotives. And the task we are working towards is producing a process/procedure that will allow the user to find/discover the best/correct settings for their particular locomotive that will give them the performance they want.

It is also important to understand that the values for a particular locomotive – make and model and scale – may not work for other locomotive … and may not even work for a ‘sister’ locomotive (one that was produced in the same run of the same make and model). And when we are talking about this kind of thing there is an assumption that the decoders are also the same make and model. Yes, certainly if you have two sister locos and you have one of them running the way you like it then you should try the same settings (CVs) for this new one … and at least use them as a starting point. But don’t be surprised if you find you have to change one or more CV values – nor even if the settings for one are significantly different from those that ‘work’ in the other one.

One of the most important aspects of a PID controller is the idea that it is not expected to achieve the "perfect" value on the first pass. It is an iterative process and will reach the targer (in our case target speed) after several successive corrections. And, precisely due to this iterative nature – the formula that is a PID controller uses the history of the past corrections … in addition to the current measurements (in our case the BEMF value that is read during the "off" segments of the PWM. The idea is to "home in" on the correct value for the PWM – and then to keep adjusting the PWM in very tiny adjustments … all with the goal of having the motor turn at a constant RPM for a given speed setting. And also with the goal of changing from any current speed step to a new speed step … smoothly (a nice steady increase or decrease in speed that results in the operator seeing his train moving in a manner that approximates what happens on a real train.

 

CV 209 is the Kp in the PID. It should usually be a low number (25 and below). Kp is the ‘current error’ value. Think of it as the ‘base value’ (size) of the error (difference between the target and the actual). But the value of CV209 is a range from 1 to 255 – so what CV 209 really represents is a "percentage" of the Kp that will be used.

CV 210 is the Ki in the PID. It should usually be a low number – and it will usually be a lower number than 209. Ki is the integral error value – that is to say that it is the sum of the past few changes (corrections). Think of it as an ‘adjustment’ to the Kp – based upon what has happened the past few times the PID value has been computed. Again the value of CV210 is not the actual value of the Ki but rather it is the percentage of the computed Ki that will be used to form the actual correction (final PID output calculation) to the PWM.

There is a "D" in the Tsunami PID controller. It is not "externalized" and Soundtraxx does not think that we, the users, should be messing with the "D" in the PID formula. The Kd in the PID calculation represents the rate of change, over time, of the PID calculation. Think of it as the slope of the curve of the error. The value for the "D" works the same way as the values for 209 and 210 … it is also a range/percent.

Turn off all momentum (CVs 3 and 4) before starting. It is probably even a good idea to just do a decoder reset.

It is highly unlikely that you will be successful in tuning the motor performance CVs correctly – if the locomotive wheels or the test track are not clean. Always start all such procedures with cleaning the wheels and track!

Use 128 speed step mode for all tuning (and running?). It is very hard for the PID controller to do its job – to provide smooth changes of speed and relatively constant RPM when the speed isn’t changing – if you only provide it with 28 steps (because each individual value represents a much larger percentage of the range of the throttle (think PWM).

CV 212 is the "intensity" of the PID calculation that will be used. Think of the PID calculation as a number. That number is actually a ‘correction’ for an error (the result of the PID calculation). If the value of 212 is 255 then 100% of that correction will be used. If the value of 212 is 128 then 50% of the correction will be used. An example will help. Let’s say that the target speed is 100, the current speed is 90. So the "error" is –10. And the PID calculation (for simplicity of this example of how 212 works) is +10. Sooooo, if 212 has a value of 128 then the PID correction, this time around, would be +5. As the value of 212 is reduced the number of iterations of the PID correction process that are required to reach a given target from a given start/error point will take longer and longer. Truly low values of 212 can produce a loco that is very ‘sluggish’ in terms of throttle response.

CV 213 is the specification of how often a BEMF measurement is taken. It is a frequency in a number of milliseconds – if the value in 213 is 23 then it takes a measurement every 23 milliseconds. Let’s use an example from real life … this is "how often does the nurse take your temperature?".

CV 214 is the duration of the BEMF ‘window’ (it is NOT the "D" in PID). It is how long the window is open. This is the "how long does the nurse leave the thermometer under your tongue?".

If you set the BEMF cut off level (CV 10) to a small value then the PID controller will be ‘in use’ over less of the entire speed range. This is, in general, a good thing. Values between 20 and 40 are recommended.

What does "starts moving" mean? Many of the tuning procedures ask you to do something until the locomotive start to move. There are 3 kinds of ‘movement’. There is the first little bit of movement – it may even be a little lurch – but the loco does not move continuously and will spend more time stopped than moving. The second phase is where the loco is moving but it may not be at a steady rate and it may not be "smooth". This is not "tie crawling" speed. The third phase is where the loco is definitely moving and is well above "tie crawling". You would still call it ‘slow’ but you wouldn’t call it very slow. For most PID tuning procedures when it says "until it starts moving" we are talking about the 2nd phase.

Locomotives should be tuned "light" (no train cars behind them). You need to know that the loco will perform well on its own. A loco with a train behind it may require more throttle in order to move at the same speed as it does light – and that’s a good thing and is a better simulation of an actual locomotive (and will sound better).

This is all I’m going to write up at this time. I intend to use this information in order to develop a procedure (or small set of procedures) that will allow you to find the best settings for the motor performance CVs - 209, 210, 212, 213, and 214 primarily … but also the BEMF cutoff, the momentum, and the trim CVs.

- Jim Betz (14 June 2010)"

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Posted by rrinker on Wednesday, March 20, 2013 2:32 PM

 Yeah but it works no better in my Stewart FT which DOES have a top quality motor and drive line. Everyone is quick to throw 3 pole motors to the wolves but every RIvarossi loco I ever came across ran nicely at slow speeds on plain DC.

            --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by mlehman on Wednesday, March 20, 2013 5:35 PM

Give the "process" that Crandell posted a try. Rather long and a little involved (you think that's bad, try reading a QSI manual!) you'll find improved results.

Like I said, my Tsunamis are all in narrowgauge steam. I've been using a group of settings that a fellow on one of my email lists developed specifically for the Blackstone C-19. They mostly run "like butter" although some minor fiddling is needed for best results, as noted above, including applying them to the BS K-27 and several brass Tsunami installs.

If you haven't given it a try, you're ignoring considerably improved response. Here's another brief example of the relevant CVs [although you will likely have to adjust for best results]:

 <CVvalue name="209" value="25" />
       <CVvalue name="210" value="20" />
       <CVvalue name="212" value="100" />   <-- with BEMF on
       <CVvalue name="217" value="2" />  <-- this value turns BEMF on

Mike Lehman

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Posted by hon30critter on Wednesday, March 20, 2013 9:17 PM

Thanks to everyone who has answered. I will try your suggestions tonight and let you know what results I get.

Just so you are aware, I have been able to make some progress by setting CV 25 to 15 which is the largest exponential speed curve preprogrammed into the decoder. With that setting I am getting some increase in the engine rpm before the locomotive moves but only if I just go to speed step 1 first. Any other throttle setting makes the engine move before the sound catches up. However, I am also sceptical that the decoder has actually accepted the exponential curve (yes - CV 29 bit 4 is set to 1) because the graph of the curve would suggest way more change in the engine's response then I am getting.

Before I go to the test track let me answer a few of your points:

Jacktal - CV 29 is set to allow for speed curves so that basic issue has been addressed. I just have to remember to change it if I have to reset the decoder because I messed up.

Wjstix - thanks for the link to the article.

Crandall - I actually think I understand everything that was in the tuning article - suprised myselfYes

David B - I recognize that the engine is not high end. However, it ran very smoothly on DC and it runs smoothly on DCC. The problem is that the decoder is applying too much power at start up. Dumpy motor or not, I should be able to dial down the decoder until nothing happens at speed step 1 (of 128) until the sound of the engine reving matches the movement. In fact, I should be able to dial the decoder down until there is no movement at all on speed step 1 - am I correct on that?

Mike - Thanks for the short version of Crandell's solution.

Richard - I have heard of JMRI's Decoder Pro many times but I have not researched it yet so I will do that in the next couple of days.

Now then - lets go see how badly I can mess up the CVsDevilSmile, Wink & GrinLaugh

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by hon30critter on Thursday, March 21, 2013 12:45 AM

An as promised update:

I think I have solved the original problem at least for now by changing CV 212 to 100. (Tom - thanks for the suggestion). The motor revs properly (at least in my uneducated opinion) before the locomotive starts to move and the relation between speed and engine noise seems appropriate.

However, now the engine seems to hesitate sporadically which it was not doing before. I think this calls for a disassembly of the gear towers to see if something has been picked up or if one of the many wires I installed for all the LEDs is interfering with moving parts before I go any further with programming.

Fun, fun, fun! Yes I am having fun but this one is proving to be a bit frustrating.

I do have another question if you don't mind. This is a bit long winded: On another thread in the prototype section I asked about the classification lights which Bachmann kindly provided clear lenses for in the H16-44. Thanks to your answers I now know that they would be different colours, or white, or off depending on the status of the train. Being obsessed with the opportunity to install LEDs I want to set the locomotive up with the option of showing either green or red or 'off' colours on the classification lights. That is simple enough using bi-colour three lead LEDs and functions 5 and 6. The problem is that the decoder only has two extra lighting functions beyond the head light and rear light controls. I need to find power for the numberboards. The best compromise I can come up with is to wire the number boards together with the headlight and rear light and then connect the negative leads for the headlight and rear light together so they will stay on regardless of the direction of the locomotive. Is this going to cause a problem? (I can live with the head and rear lights being on all the time).

Thanks

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by gandydancer19 on Thursday, March 21, 2013 9:49 AM

I don't know if your locomotive has them, but Bachmann puts in two chokes and a capacitor on the motor boards.  These cause problems when converting to DCC.  The Cap should be cut out as it is across the motor leads.  The Chokes should be removed and a shorting wire installed where they were.  These components have caused me problems on Bachmann locomotives when converted to DCC in the past.

Elmer.

The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.

(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.

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Posted by hon30critter on Thursday, March 21, 2013 4:16 PM

Thanks Elmer:

I had removed the entire original board when I started the install because there wasn't room for it and the Tsunami. I have removed the original board and hard wired all of my decoders so far. Only two of my engines have come with the factory installed pin sockets (P2Ks) and in both cases the original owners had monkeyed with the stock boards so I pitched them to be safe.

I should also mention in regard to one of David B's points that I have removed the original pick up contacts that touched the frame and wired the trucks directly to the decoder so the motor is properly isolated.

Dave

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Posted by Geared Steam on Thursday, March 21, 2013 6:45 PM

My Tsunami's motor controls are wonderful,  Its a Ford vs Chevy argument, I prefer not to attempt convince anyone different.

Mr DCC tweaks, follow the link for more than what I pasted below. 

http://www.mrdccu.com/curriculum/soundtraxx/tsunami.htm#Slow

I Can't Get My Loco to Run Well Slowly

The Tsunami has a great BEMF control system, but, like all finely tuned items, it needs to be compatible with your loco. Here's how you get them happy with each other.

  • Turn Off any speed tables with CV29
  • Set CV2 to 0
  • Shut off momentum 
    (CV3 = 0; CV4 = 0)
  • Go to Programming on the Main (OPs mode for Digitrax), preferably using DecoderPro
  • Set CV 209 to 0
  • Set CV210 to 0
  • Set the loco moving forward on speed step 1
    (128 step mode recommended)
  • Adjust Kp (CV209) until the loco just moves, very slowly - may be jerky
  • Adjust Ki (CV210) until the loco smoothes out

If you want EXTREME low speed control, you can adjust from the above settings. Bruce suggests that you reduce CV210 by 1 and then adjust CV209 up until you get movement.

To view a Windows video of what can be accomplished this way, CLICK HERE or, you can view the HD version on You Tube, just CLICK HERE!

Yes, this loco is moving on speed step 1 in 128 step mode. 
Once you have done the above, you can adjust the steam chuff rate to match the wheel rotation (assuming you aren't using a cam) by:
  • Set a medium slow speed on the loco - about step 10
  • Adjust CV116 for the proper chuff rate
    (4 chuffs per revolution for most rod locos)
The sound will be in sync for this speed step only - if the loco runs slower, it may fall off - much faster and you won't be able to count the chuffs relative to wheel rotation. Bruce finds this provides the best balance!
  • Reset momentum 
    (Bruce recommends CV3 = 40; CV4 = 20)
  • Restore speed tables

"The true sign of intelligence is not knowledge but imagination."-Albert Einstein

http://gearedsteam.blogspot.com/

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Posted by hon30critter on Thursday, March 21, 2013 11:34 PM

Geared Steam:

Thanks for sharing the process. Several sources have referred to CVs 209 and 210 as being the key to proper speed control so I will follow that route when I get the locomotive back together.

In the mean time, just to fill everyone in on the current state of this decoder installation, I took the locomotive completely apart including the trucks. There was some debris in the gears but nothing that looked big enough to interfere with their operation. (I am talking really fine particals here). I cleaned the truck parts with 99% isopropal alcohol. I then checked the gears for flash and found almost nothing so I put them back together.

Unfortunately one truck still refused to run smoothly, and in fact it developed a noticeable clunk the more I ran it. Nothing showed up under magnification when I had the truck apart so I have decided to order a new truck from Bachmann to see if it does any better.

Until I get the new truck we will have to wait to see if the Tsunami can be tamed!

Dave

 

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Posted by hon30critter on Sunday, March 24, 2013 12:57 AM

Update:

I decided to work on the defective truck to see if I could smooth it out so I set the locomotive up for DC operation and then clamped the frame into my bench vise so I could let it run. Not quite the same as having it running on track but oh well. After several hours of running at reasonably high speeds the problems with the truck went away. I have to conclude that I missed something when I had the gears apart. Either that or something got in there when I was reassembling the trucks.

With the truck apparently fixed I re-installed the decoder and went back to playing with the CVs. I am happy to report that I now have fairly good low speed performance. The engine revs up before the locomotive starts to move on speed step 1 (of 128) which is primarily what I was trying to correct in the first place. The locomotive is still slightly balky at speed step 1 but if I go to speed step 2 as soon as the engine starts to move it runs fairly smoothly and is still very slow. It is not perfect but I hope that some running time will loosen up the gears a bit more and eliminate the problem.

To those of you who suggested various CV settings, I ended up with the following:

CV 25 = 10 (Linear speed curve)

CV 29 = 50 (Speed steps enabled, DCC operation, 128 speed steps)

CV 209 = 20

CV 210 = 20

I am going to leave the locomotive set up this way for now and once I get a usable track loop set up on my layout I will put it on the track and let it run for several hours and hopefully the gears will smooth out even more.

Thanks for all the input.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by wjstix on Friday, March 29, 2013 7:57 AM

Keep in mind that AFAIK all sound decoders for diesels are set up to have the engine sound rev up as the engine starts to move. That's just the way they're designed. You can delay the start of the engine's movement so the rev-up sounds start before movement, but it sometimes takes some doing. So it's not a case that your decoder is faulty, it's just designed that way. It may be by changing so many CVs to try to get the effect you want, you've inadvertently done something that negatively affects the engine's slow speed operations.

Stix
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Posted by hon30critter on Friday, March 29, 2013 6:05 PM

WJSTIX:

The problem with the engine moving before the revs came up occurred before any changes were made to the CVs. The decoder was new, right out of the box and it did not perform realistically.

I now have it running pretty well the way I want except that it requires some more run time to smooth out the gears. If you are interested in the CV settings they are posted in a previous note in this thread.

Dave

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Posted by Mark R. on Sunday, March 31, 2013 12:58 PM

What a lot of people don't realize is that not all engines rev up before they move under all circumstances. On many engines, notch 1 does not incurr any increase in engine rpm - all it does is feed the power from the idling engine / generator to the trucks. The electricity provided by the engine at idle is sufficient to move an unloaded engine in notch 1.

If the engines are pulling a train, notch 1 is not enough to get things moving, so the throttle may be initially put into notch 3 or 4 to get things moving.

Interesting fact .... when we did the recordings for the Loksound C630M, we record ten seconds of the engine in each notch. That's when I noted that when the engine was put into notch 1, there was no change in rpm in the prime mover ! The funny part is the fact when the decoders are programmed, they purposely create an rpm increase for notch 1 because everybody "thinks" it's supposed to !

That's why engines have ground lights below the cab windows. If a throttle is inadvertantly left in notch 1, the prime mover may sound the same as it would in idle depending on the load. The ground lights are used as a visual indicator at night if the engines are creeping as they sound like they are idling.

99.99% of modellers have obviously never operated a diesel engine. I can tell you first hand that operating a real engine gives you an entirely different take on how our sound decoders should function. Listening to an engine trackside is totally different than sitting in the cab with your hands on the controls and knowing what happens with each change you make.

It was a real eye-opener for me !

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

  • Member since
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  • From: Reading, PA
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Posted by rrinker on Sunday, March 31, 2013 1:35 PM

 There's a disconnect between what people think some of us are saying and what we are actually saying. No, the prime mover does not rev when a light engine is slipped to notch 1. But neither does notch 1 do anything more than stretch some of the slack from a long freight. I fnially managed to get a cab ride and even during simple switch maneuvers the engineer was opening the throttle to notch 4 or 5 briefly before backing down just to get things moving. I still say Tsunami has this all wrong, you just can;t work it like that without resorting to manual notching which is extremely cumbersome, trying to hit function keys to simulate the throttle positon while simulataneously trunign the actual throttle knob to control train speed. Loksound is one of the ones that gets this, by the use of momentum. Setting some momentum in my locos, I can simulate the light load, no RPM increase by gradually advancing the throttle. Or, with no changes, no button pressing, I can simulate the heavy load, prime mover RPM increase with little movement effect, just by turning the throttle knob faster. It effectively ties the throttle knob to the loco throttle so I can tweak it open then back down to get the train moving without a jackrabbit start, witht he prime mover revving up to take the load and the train just creeping away from a stop.  I have yet to see a Tsunami do this, in the automatic notch mode.

 The other thing I've noticed is that steam people rave about Tsunami more than diesel people - the capabilities to alter the sounds based on BEMF load sensing seem to all be there in the steam versions, but severely lacking in diesels. Almost as if the diesel versions were afterthoughts. If they can sense the light load of a downgrade and quiet the chuffs and amplify the rod clank, why can;t they use that same load sensing to adjust the diesel prime mover mased on load rather than absolute speed, since there is rarely any direct correlation between the train speed and the prime mover?  That sort of thing would be even better than the momentum method,, although if the two worked in concert you could pretty much drive the train like the real thing, constantly adjusting the throttle to changing conditions as you go up and down hills and around curves.

           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    July 2006
  • From: Bradford, Ontario
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Posted by hon30critter on Sunday, March 31, 2013 8:16 PM

Mark and Randy:

Thanks for sharing your information.Bow

I think this is a case of "its my railroad and I will do what I want", no offense intended. I understand the logic of the real engines not reving in response to throttle notch 1 but to my uninformed eyes and ears it didn't just didn't look right. I will just have to pretend that my engineer is a little heavy handed on the throttle and doesn't bother with notch 1!Smile, Wink & Grin I'll have to turn up the volume on the coupler clank.Laugh

Dave

 

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
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  • From: Mpls/St.Paul
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Posted by wjstix on Tuesday, April 2, 2013 8:34 AM

hon30critter

WJSTIX:

The problem with the engine moving before the revs came up occurred before any changes were made to the CVs. The decoder was new, right out of the box and it did not perform realistically.

Exactly, that was my point. All sound decoders come from the factory set that way, they aren't intended to work like you want (the engine revs up before the locomotive moves). Just wanted to be sure you understood the decoder wasn't 'defective', it was just designed to work that way.

The hesitation you mentioned may be because the engine isn't picking up power from both trucks. The Bachmann engine uses a split weight, similar to many N scale engines. It can be very tricky to balance everything and keep things the way they should be when reassembling it after isolating the motor...especially the brass wipers that pick up track power.

Stix
  • Member since
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  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Tuesday, April 2, 2013 8:43 AM

 What is this 'all' you keep referring to? My Loksound and QSI decoders don;t move before the motor reves, even with stock CV settings. What the OP is referring to is the way Tsunamis do their startup on speed step 1 - in a GOOD loco it's MOVING on step 1. What you end up with is the loco moving while it's playign the 'dieel engine starting' sound, which is HUGELY annoying and most definitely incorrect behavior. That's Tsunami default out of the box, before any tweaks. The other brands of sound decoders do NOT do this as their default behavior.

 Gratned thsi can be fixed by adjusting CVs - but why is it liek this as the default? And then the use of the e-stop to do the shutdown sounds? There's 29 functions, can't you just use one of those liek everyone else does for their startup/shutdown? Starting a real loco is a specific process, so having to hit a function key to start up your loco isn;t out of line. That should also be tied to moving it - so if you don't start the engine, you can't move it. Then I guess you need a 'cut out' for a dead in tow unit since our models don;t coast.

 So many possibilities for more prototypical operation with no more than the existing technology...

                 --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    July 2006
  • From: Bradford, Ontario
  • 14,032 posts
Posted by hon30critter on Tuesday, April 2, 2013 5:41 PM

David:

I did not disregard your post. You obviously have a great deal of knowledge about DCC. However I did choose to continue to work with the engine that I have instead of scrapping the drive unit.

Right now I have the engine running acceptably and with a little run in time I hope the very minor hesitation in notch 1 will work itself out.

By the way, the first thing I did was to do away with the frame contacts and wire the trucks directly to the decoder.

Thank you for the education regarding the potential problems with the wheel wipers. I also did not know that the motor was only three poles when I bought it or I would have passed it over. Live and learn! I won't buy another older Bachmann. 

Dave

 EDIT: David, your tone bothers me. In the future, if you can't be more polite, please restrain yourself from posting to my threads.

Thankyou

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

  • Member since
    July 2006
  • From: Bradford, Ontario
  • 14,032 posts
Posted by hon30critter on Wednesday, April 3, 2013 11:54 PM

Whatever.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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