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Hi All,
I am pretty new to DCC. The other day i was operating on a very large HO layout. I could pull just about 60 loaded coal cars with my BLI AC6000. I was look to consist it with my other loco, doing it the 'easy' way by programing them under the same address. The speeds were so different that they just wouldn't run together. To make the engines run at the same speed, would you have to do something with the programing? Or is there physical work that needs to be done inside the engine? After i consist it, is there any easy why to undo it through a DCC system?
This is where your decodered engines come out on top. You have to fiddle with the speed tables in the fastest locomotive to make its throttle steps roughly the same speed as the same steps in the slower engine. So, at speed step 1, if both engines just turn their wheels at that voltage, and they are closely matched at the mid and max ranges in CV's 5 and 6 (not respectively, I believe, but the other way around), you can then MU them and they should be pretty darned close.
The easy way is to use the same brand locos (gear ratio’s are the same) with same brand and model decoders (all cv’s are the same). Everything in sink. The next way is set cv 29 to user defined speed curve and reprogram cv’s 67 to 94 trying to match the speed of each loco's with different values. Very hard to get an exact match but can be done with a lot of effort. The other way is to buy something like the QSI Quantum programmer or maybe there’s something free that can be used that sets the cv’s for you.
I run same brands loco’s with same model decoders, works perfect.
Like the other guys were saying, your going to have to program some CVs. Ususally it involves, CVs 2, 5, and 6 (start, mid, and max respectively). If your going to use the BLI AC6000 as your leader, try to match the second locomotive to its speed. Start out with them a few inches apart and toggle between them. start out slow and eventually youll see that adjusting CVs 2, 5, and 6 will get the 2nd locomotive matched up to the first one pretty well.
That being said, there are some locomotives you just cant get to speed match at all (at least well). For me, I havent been able to get my Athearn SW1500 switcher with a Digitrax sound decoder to match to my Atlas Trainman GP38-2 with a NCE decoder no matter what I try. Ive head that some Proto locos wont match bc of the drive or other factors.
Uhhh...sort of. You basically want to establish one of the engines as kind of a baseline, and then adjust the other engine to it so that the both run at the same speeds throughout their speed range. Now that doesnt mean you wont have to change some of the CV settings for your "Baseline" engine for optimum preformance. Confusing huh?
Use a pad of paper and pencil and prepared to be patient the first time you do this. Record the changes you make to each CV (2, 5, and 6) and youll eventually get it.
This is just the way Ive approached speed matching with different models locos. It doesnt mean its the right way or that there isnt a better way.
Of course, you could just sell me that T55 on the cheap for all these words of wisdom. Hehe...
Between the two engines, the T55 is going to have the smoother drive, although the BLI's is nice too. I would start by slowing the BLI down. Do this by raising the value of CV 2 (start voltage) of the BLI to say 5. You want it to just start to crawl (not jump) at speed step 1. (I use 28 speed steps, I just find it easier). If that doesnt slow it down, then keep raising CV 2 in increments of 5 until it does. At some point, if you keep raising CV 2, you'll have to raise CV 5 (Mid voltage) a proportional amount. This CV is usu set at 128 (halfway to 255) which is what CV 6 (max) is usually at.
Okay,
I would like to use the BLI as the lead because i like the sound better. So if i would decrease the momentum to slow the BLI down, i would increase the momentum to speed the T55 up?
I found it easier to take the slower of the loco's and match the other to it. I have kato, atlas, p2k, athearn genesis, blue box, and rr all speed matched. I start with all locos making them creep (as mentioned above) using cv2. After that I take both loco's and MU them together. I set them 2-3 inches apart and turn the throttle to 1/2 way. (It helps if they don't couple together) Ok take the fastest loco and read cv 6. Say it says 200, try 150 and repeat the speed test. I do this till I get it real close. Then I repeat that for cv5 (top voltage) using 100% on the throttle when I spped test them. I have some loco's with cv6 at 90 and cv5 at 150. That's what it takes but I have MU'd all kinds of manufacturers together with great success. On a side note. I have spent an hour on some of my loco's to get them to "play well with others".
Got a computer available? Install JMRI and use Decoderpro - Makes this stuff not only easy (save multiple configs with notes etc) but IMO, fun rather than a chore.... It becomes easy to set complete speed curves rather than the less accurate "start, mid and full" CV's only - Fine tuning along with no knowledge of the actual CV's you're tweaking is, IMHO, awesome.
Is there anything in DCC that supports the system knowing which engine is in front and providing it a bit more power than the training engines? My understanding is that's how real consists work.
Well I was thinking about a system where you perhaps identify the arrangement of the engines so that when you reverse direction it automatically adjusts power so that the new leading engine applies more force.
________ Curvy Cams
Well I was thinking about a system where you perhaps identify the arrangement of the engines so that when you reverse direction it automatically adjusts power so that the new leading engine applies more force.
Well I was thinking about a system where you perhaps identify the arrangement of the engines so that when you reverse direction it automatically adjusts power so that the new leading engine applies more force.
Not really necessary. The goal is to get all of them as identical as possible. The DCC system does not give the lead engine more power than the others.
Got a computer available? Install JMRI and use Decoderpro - Makes this stuff not only easy (save multiple configs with notes etc) but IMO, fun rather than a chore.... It becomes easy to set complete speed curves rather than the less accurate "start, mid and full" CV's only - Fine tuning along with no knowledge of the actual CV's you're tweaking is, IMHO, awesome.
The singular time I've consisted locos was with one of those big NCE CAB throttles. It asked me what the primary loco was, I added a loco and had to specify its direction relative to the first. I assume more would be the same.
If the software assumed that loco 1 was at one end of the consist and facing away from the other locos and each consecutive loco was attached numerically in order then it shouldn't be too big of a deal for the software to just know "FWD = give loco 1 an extra volt" and "REV = give last loco an extra volt", or whatever you predefine as the added boost for the 'lead' loco.
I just don't know if the software currently makes such assumptions or can be told specifics about the consist. What if you're weird and run a consist of two locos with their noses together?
________ Lovely Wendie99
The singular time I've consisted locos was with one of those big NCE CAB throttles. It asked me what the primary loco was, I added a loco and had to specify its direction relative to the first. I assume more would be the same.
NCE makes consisting very straightforward. We use that at our club and it's a good system.
If the software assumed that loco 1 was at one end of the consist and facing away from the other locos and each consecutive loco was attached numerically in order then it shouldn't be too big of a deal for the software to just know "FWD = give loco 1 an extra volt" and "REV = give last loco an extra volt", or whatever you predefine as the added boost for the 'lead' loco.
Because there's really no requirement to. You want them the same. Also, the DCC system doesn't know or care what order the locos are in. It uses the lead engine to reference the consist (so instead of remembering the consist address you can just address it by the engine #), and each other engine is simply told (when setting up the consist) that it's in the consist and will respond to commands sent to the consist address. You can add or remove engines to the consist; it doesn't care (or know) what order.
I just don't know if the software currently makes such assumptions or can be told specifics about the consist. What if you're weird and run a consist of two locos with their noses together?
