DCC Unpredictable

Hytec Nov 5, 2019

  1. Hytec

    Hytec TrainBoard Member

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    OK, the title is not fair, but it is for me and I need help. :)

    I've been a contented DC Dinosaur for 72 years. I'm now is experimenting with DCC and am frustrated by its unpredictability in my situation. Though to be fair my situation may be rare, if not unique. I'm trying to build a small fun (test) layout with HO trolleys running under a hot wire power system.

    My problem is intermittent and/or no operation. The intermittent operation I attribute to dirty wire and track because the cars have moved, albeit jerkily and cleaning both wire and track helped somewhat. The no operation throws me for a loop because when I restart the controller after a few hours, place a previously working car on the track and wire, and energize it, I get no response, even moving it back and forth. This confuses me because with dirty track and wire something should occur even for a second or two.

    My question is, will a decoder lock itself into a self-protect mode to prevent circuit damage when it detects intermittent power? If so, is there a way to reboot or reset the decoder to get it back to an initial state?

    My personal problem is that I retired after 40+ designing computers and systems, so I can visualize what is probably happening within the decoder architecture. But I can find no information on how decoders are designed, or descriptions on how to interact with them. Can anybody help, or give me a direction to start looking for more information?

    The trolleys are Bowser products that use ESU Loksound V4.0 decoders. The controller is an ESU ECoS II 50210.

    Thanks for any help whatsoever. (y)
     
  2. Point353

    Point353 TrainBoard Member

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  3. wvgca

    wvgca TrainBoard Member

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    i have only been in DCC for a while [maybe eight years], but i find it very predicatable ... sorry, nothing to do with your situation....
     
  4. RBrodzinsky

    RBrodzinsky November 18, 2022 Staff Member TrainBoard Supporter In Memoriam

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    Hank,

    Probably not the decoders, ESU LokSounds are very reliable (yes, you can kill them). More likely culprit is going to be the DCC signal. Yep, dirty track / wire is the main item to look at, but also very important for DCC is quality of the signal.

    DCC is a pulse modulated square wave AC signal, so is susceptible to degradation. Make sure you have power drops from the track/wire to buss at about 4’ to 6’ intervals, and do not rely on rail joiners to conduct signal between track sections.

    On the ECoS, make sure you have a full voltage signal for your scale on the output. HO should be set for 14V (and I usually recommend even N scale to be set there).
     
  5. COverton

    COverton TrainBoard Supporter

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    As far as I have seen and read, there is no thermal or logic protection on decoders. If they get a long-enough break in power supply, they go into 'restart' mode. They'll start again with start-up sounds like hatches being opened, fire building, pumps going, diesel being primed and turned over, and other neutral standing sounds until fully up and running and ready for a speed step.

    Intermittent performance is generally due to inadequate voltage or signal, and the two go together; insufficient voltage means a weak digital signal, and the decoder acts up. What can cause the poor voltage is a mystery often, but it can be one of the following, exclusive of some mechanical problems with motors and lubes, added near the end of this list:

    a. bad power supply;
    b. bad circuit board in the base station;
    c. bad wire in the cord between hand-held throttle and base station, or bad connectors;
    d. faulty hand-held circuitry or board;
    e. dirty tracks, or heavily oxidized rails;
    f. weak power supply to tracks, often due to bad connections or faulty solders;
    g. dirty tire surfaces on wheels intended to pass power on to the decoder;
    h dirty wipers, or oxidized wipers, or bent wipers, or displaced wipers not making solid contact with axles or backs of wheels;
    i. bad solders or broken wires internal to the locomotive intended to pass power to the decoder;
    j. bad solders or connections from the decoder to the motor and/or lights;
    l. bad decoder;
    m. old or hard lubes, inadequate lubes in the gear tower or final drives;
    n. bad gears, split gears that bind or spin on axles; and
    o. bad motor
     
  6. Hytec

    Hytec TrainBoard Member

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    Aha, I saw a reference to output voltage. Having no experience, I didn't even look at it, though I saw something about it in setup. Thanks, I'll see what it's set at and change if needed. What's your opinion of 18V? Thanks.

    BTW, trolley wire connection is direct through clip leads. Though I'd better check track return. I forget how I wired it.

    I'm so used to DC that I didn't think about digital communications and decay due to impedance...DUH! Thanks for giving me a wake up call back to computer communication. Boy, I'm embarrassed. :oops:

    Stay tuned, I will be back. LOL
     
  7. tjdreams

    tjdreams TrainBoard Member

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    Have you downloaded the ESU Instruction Manual? If not go to the ESU website under Downloads click on Instruction Manuals, scroll down and find the one for your decoder, click download , accept the terms then open the file once it downloads you will find a tone of useful info about programing and resetting the decoder.
    http://www.esu.eu/en/downloads/instruction-manuals/digital-decoders/

    Dirty track can cause all kinds of crazy reactions from the decoder Believe me I model Z scale where a single speck of dust can lift the entire truck breaking contact causing hesitation intermittent stop / go operation, the sound sequence to repeatedly restart and it can freeze up or even kill a decoder. More likely though is the stop and go jerking motion could have caused a wire to come loose or the decoder to become partially unplugged. Try taking the shell/body off and make sure everything is still properly connected.

    David
     
  8. Hytec

    Hytec TrainBoard Member

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    David, thank you. That looks like the information I've been looking for. It'll take a while to study it. Though I suspect it has what I need.
     
  9. RBrodzinsky

    RBrodzinsky November 18, 2022 Staff Member TrainBoard Supporter In Memoriam

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    18V is probably too high. I would stay at 15V max for HO. If larger scale, inch up until you get good results, after checking the stuff below.

    Yeah, knowing your background, I figured a few technical terms would be all you needed for an AHA moment. Signal degradation is a primary cause of poor performance, particularly when a person is switching from DC.
     
  10. dalebaker

    dalebaker TrainBoard Member

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    I’ll throw something else out there. You might try a conductive lubricant on the contacts for the cantenary. I have used it with good success on balky locomotives in the past. Another product I use on the rails is called Never Stall, it works pretty good.
     
    Jimbo20 likes this.
  11. Hytec

    Hytec TrainBoard Member

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    Thanks guys, I'll work with all this and get back to you.
     
  12. Hytec

    Hytec TrainBoard Member

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    Success...sort of. After intense cleaning of wire and rail with LaBelle 106, plus clip lead power shunts directly to the wire and rail, the cars operated jerkily with some manual encouragement.

    George Huckaby (Custom-Traxx) had advised me against using 28AWG nickel silver wire, but since I already had some. Hindsight = Regret. :(

    However, I found a roll of 26AWG phosphor-bronze wire in a junk box, which after intense cleaning to remove about 50 years of crud, worked much better on a test span.

    One thing I have observed is that DCC power through the trolley poles appears to be less reliable than DCC power through the wheels. Ah well, I did say that this effort is an experiment, and as often heard on Myth Busters, "Failure is always an option." LOL

    Thanks for all your help.
     
  13. DCESharkman

    DCESharkman TrainBoard Member

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    The trolley poles tend to oxidize much faster because of the constant exposure to air on all surfaces.
     
  14. Hytec

    Hytec TrainBoard Member

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    I just hung 8-10 feet of 26 AWG Phosphor-Bronze after cleaning it until it was bright and shiny. I cleaned the rails under the new wire. Then I cleaned the pole shoe and the pole socket, and lubed them with LaBelle 105. Wow, it moved, OK, just slightly until it sputtered to a stop, but it moved. (y)

    Then I found a spot where it would run reliably while I held it so the wheels would polish. After all this, it ran for 6-8 inches before it sputtered to a stop. Hey, that's progress. :cool:

    Question - can the ESU DCC board modified for Bowser trolleys operate on DC without damage? If so, then I'd be happy just getting the car to run a loop under wire. I know if I asked Bowser the answer would be NO, because of warranty issues. But this is my experiment. If it fails the smoke test, then it's my problem, not theirs.

    BTW, I took everyone's advice about DCC signal strength and continuity. I fed power from a bus to the poles and track every few feet.

    This is a fun challenge and it keeps me off the streets at night...;)
     
  15. RBrodzinsky

    RBrodzinsky November 18, 2022 Staff Member TrainBoard Supporter In Memoriam

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    The V4 decoders do support DC operations. You don’t get function control (horns, whistles, etc), but basic motor sounds can work
     
  16. Hytec

    Hytec TrainBoard Member

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    That's great. All I want is for the car to run around the loop without hiccuping. Don't care about that other stuff. I've been happy running DC since 1947. Don't see any reason to change now. :D

    Thanks
     
  17. catfan

    catfan TrainBoard Member

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    Hank!

    Please don't abandon DCC after one failure. DCC has proven it's self many times over. Having read about your past computer skills, I'm amazed that you are not leading the pack in this respective. Are we correct in presuming that your first failure out of the gate was a trolley with duel path feed via photograph to rail? That's a pretty tough endeavor for even the seasoned DCC folks. Rewire your bus to connect to the inner and outer loops and see what happens.
     
  18. dalebaker

    dalebaker TrainBoard Member

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    Have you cleaned the wheels on the trolly? Simple, but can be a culprit.
    I do not know if Labelle 105 is conductive. I had to order a conductive lube special. Again, I would look at Never-Stall as well. I’ve had tremendous success with that on balky locomotives.
     

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