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Lead Loco Straining to Pull Another DCC Locomotive in Consist

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Lead Loco Straining to Pull Another DCC Locomotive in Consist
Posted by Coastie71 on Friday, June 10, 2022 7:18 PM

I've recently purchased two additional SD50 Walthers Mainline HO locomotives.  I already had one I purchased 2 years ago along with an Athearn Ready-to-Roll.  Had previous purchased locos, one pulling a 15 car string of coal hoppers and the other a 20 car string (all cars have metal wheels and are very light to pull).  Neither loco had any problems pulling these cars and the Athearn loco actually was much more responsive (quick to move at much lower speeds) than the Walthers Mainline one.  I setup the two Walthers Mainline locos (previous and new one) in a consist and it appears they are running fine.  However, when setting up the Athearn and the other new Mainline together in a consist, with the Athearn as the lead loco, the Athearn seems to be straining to pull the Mainline and the hopper cars as if the Mainline is not doing its share of pulling power.  A couple of times (I think I need to get matching couplers) as the Athearn loco separated from Mainline in spots where they take a slight bump when crossing and it sped away much faster from the Mainline pulling the string of cars.

I'm assuming it probably has to do with speed steps being different, but I'm not someone who messes with them or CVs in general except to assign the address to the loco number, and I did try to increase volumes on most of my locos due to my bad hearing.  Didn't always have good luck doing that and had to reset to factory settings on these previous purchased locos as well as others I have.  I do have a separate programming track that is not attached to the main.

Looking for whatever help anybody can provide.

PS  I really would like to keep the Athearn as the lead loco in the consist as the Econami Sound Decoder is much better and louder than the ESU ones on the Mainlines (I can barely hear the horn on them and cannot hear the bells at all unless I put my ear right next to them).

Thanks

Gary (Coastie71)

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Posted by MisterBeasley on Friday, June 10, 2022 8:24 PM

To use two DCC engines in a consist, they should be speed-matched as best as you can do.  It involves setting a few CVs, and it can be an iterative process.  Your engines are not speed matched.  I can tell from your description.

It takes an iron man to play with a toy iron horse. 

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Posted by hjQi on Friday, June 10, 2022 9:40 PM

You need to do speed match. Locos from a same manufacturer have the same decoder so you might be ok. But when locos from different manufactuers, if they use different decoders, the decoders setting might be different. Then their speeds might be different with the same DCC input...

Jerry

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Posted by "JaBear" on Friday, June 10, 2022 9:57 PM
Gidday Gary, Mr. B and Jerry are right, not all locomotives are created equal, so speed matching is required.
 
Here’s a link to Engineer Google…
 
 
But there is a cheat depending on the system and throttle you have! My running of locomotives, pre Covid, was on an exhibition layout at train shows, and having a Digitrax DT500 throttle which allowed direct control of two locomotives at the same time, meant that I could set the throttles to two different settings to get both locomotives pulling at the same speed.
Hope this helps,
Cheers, the Bear.Smile

"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."

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Posted by dehusman on Friday, June 10, 2022 11:30 PM

Just as a test, leave teh units in the same consist.

If you have double track, put one on one track and one on the other, side by side.

If you don't have double track try a main and a siding or main and a yard track, or put them on the same track, separated a foot or two. 

Then try running them.  Does one run away or catch up to the other?

Dave H. Painted side goes up. My website : wnbranch.com

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Posted by Coastie71 on Saturday, June 11, 2022 1:51 PM

I'm responding to everyone's input and I really appreciate everyone's good advice and help and the link to the video's explaining speed matching.  I'll take a look at them shortly and hopefully can get a better understanding how to modify the CVs to do this.

I'll also try running the loco's on my double mainlines to see how much they differ.

I have a Digitrax system and I'm using a DT602 throttle (matter of fact I bought two of them) so I can run other locos with them without having to pull up the other locos on the same throttle.  If I can't get the speed matched I'll try to use one of the throttles to control the locos in the same consist.

Again, thanks for everyone's help.

Gary (Coastie71)

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Posted by Coastie71 on Sunday, June 12, 2022 2:06 PM

I've tried to read up on how to speed match and it appears to be very complicated, at lease it is to me.  Although I noticed that the use of DecoderPro can make the process easier, trying to understand how to use that software also appears to be very difficult if you're not familiar with its use.

I noted the youtube video that metioned modifying CV2, CV6 and CV5 as a rough method to speed match, but other videos or documentation said that would not work correctly or when locos go in reverse.

Tried to determine if DecoderPro will work on my Digitrax DCS210+ command station and noted it wasn't listed in the support page.  I also don't have a laptop, only tower units, but the computer I was hoping to use has only Windows XP and looks like that would only support very early versions of DecoderPro.  I do have another one with Windows 7, but I use that one specifically for the printer I have.  I would have to download required software and lug that computer out to the building that has the layout as I can't get a good WiFi signal out in the steel building.

Any additional guidance or suggestion would be appreciated on getting the locos speed matched.

Thanks again, Gary (Coastie71)

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Posted by snjroy on Sunday, June 12, 2022 3:36 PM

The moderators should move this to the DCC section.

Harry, using CVs 2, 6 and 5 will work in most situations. I suggest you give it a try.

Simon

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Posted by hjQi on Sunday, June 12, 2022 10:29 PM

You can buy an Accutrack II Speedometer that you can use with DecoderPro together to help you match the speed more precisely. Here is the youtube video I used to learn how to do speed match.

https://www.youtube.com/watch?v=g0HyUdH0dq8

In DecoderPro, you need to use 28 step speed table. This video explains how you can match the 28 step speed table to your throttle reading and speed.

Be patient. Once you learn, you can create an excel sheet to help you match the speed. Once you do the first match, the rest will be much easier.

The time for matching speed also depends on the decoder. I found LokSound, LokPilot, and SoundTraxx decoders are very easy to match. I have a few times that I simply copy the speed table from one loco to another then adjust only the Vhigh. This takes me less than 10min to match all the speed. Some other decoders are hard to match but normally I can finish in 30min.

DCS 210+ is great as it has a USB port that you can connect to your computer directly. DecoderPro is not that hard to use and just watch the youtube video above. It also helps you maintain a list of locos. I think the only issue you have now is to find a good computer. A cheap laptop (~$400) would do the job for you... I am using a 6 year old macbook air and it works very well for me.

Good luck!

Jerry

 

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Posted by jjdamnit on Tuesday, June 14, 2022 1:40 PM

Hello All,

I recommend getting the Digitrax Big Book Of DCC.

This is an extremely useful addition to the model railroading library for anyone using DCC, no matter the system.

Coastie71
If I can't get the speed matched I'll try to use one of the throttles to control the locos in the same consist.

I doubt that will give you the results you are seeking.

Here's why...

There are three main types of consisting, regardless of speed matching. All have their advantages and disadvantages:

  • Basic:
    All locomotives in the consist have the same address. When the command station sends out control packets all units respond the same; lights, speed, and sounds respond equally. The drawback of this type of consist is all the locomotives with the same address "think" they are the same. If you never plan to break this consist apart this is a viable option. An advantage is you can take this consist to another layout, using the same or a different DCC manufacturer, as long as the asssigned two (2) or four (4) digit address isn't taken you can run this consist on a different layout. Your can have as many locomotives in this type of consist only being limited to the number of locomotives your DCC systems power can support.

  • Advanced:
    This type of consisting is dependent on the Decoder(s) architecture and the ability to support CV19. The decoder(s) are assigned to a consist address separate from their individual address. The advantage is this consist can be broken apart and each separate unit will respond to its individual address. Also, certain units in an advanced consist can be programmed to respond to lights and sound functions independently. If you move this consist to another layout you need to remember the order and direction of each locomotive. There can be a limit to how many consists exist and how many locomotives can be assigned to each consist. This is dependent on the individual DCC manufacturer.

  • Universal:
    This type of consist is held or "remembered" in the individual command station. It is sometimes referred to as "Old" or "Brute" consisting. Some DCC systems there is a limited number of locomotives you can have in this type of consist along with a limit on the number of consists you can create. 

No matter which consisting method you choose, for trouble-free operation you still want to have all units speed matched.

Speed matching is dependent on the architecture of the decoder.

For example; Bachmann, non-sound decoders do not support CVs 5 or 6 (V Max & V Mid) which are necessary to speed matching.

On my pike I have several consists, all use advance consisting.

  • A four-unit consist of GP40s
  • A three-unit consist of GP30s
  • A Cow & Calf NW2 switching consist
  • A MOW snow plow train with an F7B & RS3

Each consist has been re-motored with the same motors and decoders (with the exception of the F7B & RS3; which are speed matched only).

When you begin to mix and match locomotives, even of the same type, and manufacturer, the difference in the production dates can influence gear ratios and decoder types.

There is a lot of mystique surrounding speed matching.

Even after standardizing motors and decoders in my consists some fine-tuning was necessary for optimal operation and enjoyment.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by Coastie71 on Wednesday, June 15, 2022 2:28 PM

I want to thank everyone who provided additional guidance and instructions.  I was able to get my old Windows 7 desktop computer with the latest 4.26 version of DecoderPro working with my DCS210+.  Sure wish Digitrax had guidance on their site to tell you that you need drivers and that the PR3/PR4 drivers are the ones needed.

I watched some of the videos you guys sent and others on speed matching.  I think I got the general/basic idea, but of course I'm still hesitant that I'll mess something up and can't fix it with reseting to factory default.

I was supprised that alot of the locos did't pullup the exact decoder when read from the decoder when setting up the roster.  I'm hoping that I picked the right ones from the many choices.  I wish the documentation that came with locos and sites I bought the locos from gave more specifics on the decoders.  I'm only going to be speed matching two sets of SD50s (two CSX  and two NS locos) and plan on keeping those consists together at all times.  I'm not sure if I want to spend the money for the speed reading device just for these two consists.  I'm not really concerned on the speeds being actual speeds for the type of locos as long as two concisted locos startup and travel at around the same speeds.

Again, I really appreciate all the help you guys provided and sure am glad this community is so engaged on helping others who are fairly new to model railroading and DCC especially.

Thanks again, Gary (Coastie71)

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Posted by wrench567 on Wednesday, June 15, 2022 3:16 PM

  Coastie71.

  In my experience consisting different locomotive and decoders I have found using the 3 speed control CVs and adding a bit of momentum is a whole lot easier than the speed curves.

CV2 Starting voltage. I always put 0.

CV5 top speed voltage. Adjust this first on the fastest engine to make the pair top out at the same time. Don't try to speed up the slower one.

CV6 mid range speed. The hire the number the faster acceleration.

  Momentum CVs. 3 and 4. Somewhere around 20 for the ESU decoders and maybe more for Tsunami.

  The ESU decoders have something called delaid start. This let's the engine sound rev up before it starts moving. I will have to get back to you about disabling that.

    Pete

 

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Posted by jjdamnit on Wednesday, June 15, 2022 4:05 PM

Hello All,

Coastie71
Sure wish Digitrax had guidance on their site to tell you that you need drivers and that the PR3/PR4 drivers are the ones needed.

For this info, you will need to go to the DecoderPro webpages and look up how to install on a PC.

The JMRI web page is fairly detailed and does have info on what drivers are needed.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by wrench567 on Wednesday, June 15, 2022 4:18 PM

  Sorry. My laptop was in the middle of an update and my programmer will not work until it's done.

 To disable the delayed start on the ESU decoders change CV124 to 0. That is if the tsunami starts moving before the ESU decoders.

    Pete.

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Posted by hjQi on Wednesday, June 15, 2022 10:22 PM

Coastie71
I'm only going to be speed matching two sets of SD50s (two CSX and two NS locos) and plan on keeping those consists together at all times.

Actually, speed matching has the benfit beyond consisting. In the youtube video I posted in response to your question, one big advantage of speed matching is that all your locos will run at about the same speed for the same throttle input. For example, by using speed matching, all my locos run at 50MPH when I turn my throttle to 50. Most my locos have a maximum speed of 50MPH, except for some haulers for passenger cars.

If you have or plan to have lots of DCC locos, I think AccuTrack Speedometer (less than $100) is a good investment.

Jerry

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Posted by wjstix on Thursday, June 16, 2022 4:24 PM

To get the two engines to run together, you just need the speeds to be close (within 5-10%). You really only need to change CV5. If CV6 is left at zero, it turns it off, and the decoder sets up a straight line between the amount you set CV5 (top speed) to and the amount in CV2 (speed at step 1 - which should also be set to zero). 

Try setting CV5 on the fast engine to say 200 which will reduce the speed about 20% and run the two engines and see how they do. If it's still too fast, reduce it to say 150 and test again. If it's now too slow, increase to maybe 180. It's a little bit of trial-and-error, but pretty soon they will be close.

BTW re sound - the decoder will have a master volume CV that you can turn all the way up, you don't need to do each individual sound to increase the volume. 

Stix
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Posted by Coastie71 on Saturday, June 18, 2022 4:09 PM

Wow, thanks again for everyone's input.  Sorry for the late response, but been sick past few days.  I'm going to try some of these methods, the simplier ones first.  If I run into problems I'll be back of course.

I did try increasing the master volume before I got the DecoderPro on most of my locos, but ran into trouble with some when I was trying to do adjustment for the horn, bell and not the others.  The problem I noted with the master volume increase, it makes the sound of the train moving and idiling much louder which also plays into why I can't hear the bell and horn.  Probably should get those hearing aids that everyone keeps telling me to get.

Again, I really appreciate everyone's help.

Thanks, Gary (Coastie71)

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Posted by wjstix on Tuesday, June 21, 2022 3:20 PM

I find most sound decoders come with the horn or whistle too soft compared to the other sounds. I lived near a train line for many years, and the first sound you hear of a coming train is that loud diesel airhorn.

What I generally do to start up setting sound volumes is to set the horn to 100%, then set all the others to about 60%. Then I adjust the main volume up or down as needed so it's 'loud enough' without being too loud or distorting.

BTW this is much easier to do with Decoder Pro than doing one CV at a time. I use a Digitrax PR4 to connect a programming track to my laptop. JMRI Decoder Pro is a free download.

Stix
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Posted by Coastie71 on Tuesday, June 21, 2022 4:09 PM

Stix thanks for your help on the sound levels.  I'll give it a try.

This is to anyone who looks at this comment, but I'm still not sure that DecoderPro is reading the right decoder when I select read from the decoder.  Example:  I recently purchased two Rapido F40PH locos and just tried to have them inputed into DecoderPro and it selected ESU LockSound 5 DCC and 5 FX DCC, but the manual and Rapido's websiste indicates to use the ESU Locksound Select manual and nothint about Locksound 5, so is DecoderPro selecting the wrong decoder or is Rapido manual/website incorrect.

I'm also unsure if I'm actually selecting the right decoders for all my other trains, espcially when I get way too many choices and can't get any specific information from the manual, etc.  I'm afraid I'm selecting the wrong decoder or not specific decoder and therefore, not really getting the right settings for the actual installed decoder, which in turn will cause more problems that solve, especially when speed matching.

When I ask the DecoderPro to read all the info from the actual loco decoder is it populating DecoderPro with that information or is it still the information from whatever decoder I selected when the loco was first populated into DecoderPro based on the decoder it said it was or might be or that I choose from the list of possible choices.

Holding off on doing any adjustments until someone can clarify how DecoderPro is reading the actual decoder, even if I select the wrong decoder or DecoderPro does when first put into the program.

Thanks again for everyones help, I really appreciate it.

Gary (Coastie71)

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Posted by Bayway Terminal on Thursday, June 23, 2022 12:22 PM

Agree with Jerry on consisting same Mfg engines, otherwise be prepared to get your DCC controller & decoder manuals out and follow CV setting instructions on speed matching.  I recently purchased two SC ES44's that when double headed run like a clock out of the box, compared to all the time i spent attempting to speed match dissimilar engines, including same brand mfg engines with different tooling or dissimilar decoders?  Bayway Terminal NJ

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Posted by maxman on Thursday, June 23, 2022 3:50 PM

Coastie71
Holding off on doing any adjustments until someone can clarify how DecoderPro is reading the actual decoder, even if I select the wrong decoder or DecoderPro does when first put into the program.

Assuming you are starting from scratch rather than "assuming" what you have, according to google "CV7 holds the manufacturer's software revision codes. CV8 holds the NMRA assigned Manufacturer code. Reading the contents of these registers will let you determine what decoder is in the locomotive without having to open it up."

Someone has programmed DecoderPro to read this info and point to the appropriate decoder.

And please realize that if DecoderPro gives you a bunch of choices for a Digitrax xbn69.98 and your loco is not one of them, that doesn't mean very much.  This is because all (most?) of the decoder manufacturers have only one general Diesel Loco mobile decoder manual and one Users Manual.

These cover all the various CVs and the way they are supposed to work.  They are  not made specifically for every loco out there.

Where things usually do change is when whomever manufactures the loco, Athearn for example, purchases the decoder to have it installed in whatever they are making, and asks the decoder provider to have different default values in the CVs, or have the CVs do different functions.  For this information you need the "users guide" or "quick start guide" that should be in the box your new loco came in.

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Posted by hjQi on Thursday, June 23, 2022 10:01 PM

Coastie71
I'm still hesitant that I'll mess something up and can't fix it with reseting to factory default.

Don't worry about this. This probably never happen. If something goes wrong, it must have a reason and you can ask in the DCC forum.

Coastie71
I'm hoping that I picked the right ones from the many choices. I wish the documentation that came with locos and sites I bought the locos from gave more specifics on the decoders.

Many times, it doesn't matter too much if DecoderPro picks a decoder that does not match what it should be. I am also glad to see that you notice the documentation is so simple with so few information, or so generic.Sad I have a few Atlas locos that came with no nothing. My feeling is that lots of part of this hobby is DIY based. So we are supposed to know things what we actually don't know. But the nice thing is that we have lots of very knowledgeable people who are willing to help on this forum and in this hobby...

Have fun!

Jerry

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Posted by wjstix on Friday, June 24, 2022 9:17 AM

I think the manufacturers are kinda caught in the middle. It used to be you had virtually a book of instructions of how to program every single thing on a decoder, including how to set "bits" of CVs etc. Unfortunately, this had the effect of scaring off a lot of people who felt like they couldn't be in DCC unless they had a degree in computer programming (a comment often made on the forum over the years).

So the manufacturers worked to have decoders come with default settings so say a sound equipped engine only needed the ID number and perhaps the basic speed and momentum CVs changed to allow the engine to run and sound good. Often now they just include a few basic instructions about settings and then say "see our (or the decoder maker's) website for more information" - and steer you to a website with instructions that sometimes are far from clear.

Stix
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Posted by Coastie71 on Friday, June 24, 2022 1:35 PM

Thanks everyone for their assistance and guidance.  I took the Decoder Pro questions to the DCC forum as someone said that its where it should be.  I know I'm talking to some of you on that discussion topic in the other forum, so I'll address any further questions there.

Thanks again, Gary (Coastie71)

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