NCE POWER CAB - DECODER RECOMMENDATIONS

Zscaleplanet Dec 5, 2020

  1. rray

    rray Staff Member

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    For the most part, decoders all work OK. Some have different extra features to help get balky high current locomotives running, or to make the speed the same going up a hill, etc. In Z, we usually have to hunt down the responsible CV codes to turn off those features or our locomotives might take off like a rocket suddenly, run way too fast all the time, or not be able to fully stop.

    Then there are other features like the ability to add super cap inputs, which help a loco run while loosing electrical pickup, and keep lights from flickering. There's transponding and rail com which send pings out to tell special detectors where the locomotive is on our layout. Then there are extra lights, various special flashing light effects like ditch lights or beacons, and in larger decoders there is sound.

    So people often select decoders by the features they want. In Z, we often focus on the smallest size instead of features, but I look for the balance, and ease of programming. I avoid decoders that are difficult to program like Tran decoders, even though they have the smallest size. Turning off those special motor functions that turn Z Scale low current locomotives into ballistic mode rockets is a priority for me. And they can be difficult to find.
     
  2. husafreak

    husafreak TrainBoard Member

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    I would like to know more about "super caps" or the "Power1 supercap module" as a quick google search does not pull up anything for Z scalers. I know we are basically talking about the energy storage property of capacitors. It's like having a battery on board, so the current from the tracks charges the battery which powers the loco with a small reserve of power to smooth out or dampen electrical fluctuations. Maybe that is what my TCS AZL4 equipped loco's need, because I have played with the contacts to the board and wipers so much that I know there is nothing left I can do and the lights still flicker. Options now are to try other boards, hard wiring, or perhaps I could fit a cap in there...
     
  3. husafreak

    husafreak TrainBoard Member

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  4. husafreak

    husafreak TrainBoard Member

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    Yikes! Well at least I tried ;) Anywhoo, this was a reply I got this morning from the Streamlined Backshop. But so far my favorite comment in this discussion is from Robert regarding the Digitrax DZ126T: "they just work". So I ordered a couple of those as well ;)
     
    Last edited: Dec 24, 2020
  5. minesweeper

    minesweeper TrainBoard Member

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    I model HO, but my experience can be applied in all scales.
    I had a model with an European Plux 22 plug, got a lokpilot 5.
    What happened is that the LP5 has so many functionalities (not functions) that require very complex CV input unless you have an ESU control station or use their programming software.
    Also, the defaults were different than others, so when I got it plugged all lights outputs had fancy effects. Since I have a NCE power cab and a Mac laptop (and the manual at that time was only in German), I had to bring it to a retailer (luckily I AM in Germany, then it was close).
    He saw the decoder was working properly, but had to leave the whole model to him to have the functions correctly mapped to the PCB wiring.
    If no sound and fancy functions are needed I would keep the NCE, these work great and are simple to program.

    Inviato dal mio Nokia 5.3 utilizzando Tapatalk
     
  6. SJ Z-man

    SJ Z-man TrainBoard Member

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    for *any* SuperCap or Capacitor banks (See: Zmodell), they will need to be in a B-unit, Boxcar or Tender (if the decoder is in the Cab). The Caps are big and always mutliple caps on a PC board. Then, you have to determine where the + and - connections are on the decoder, so you can solder wires to it.

    Clean your wheels, *then* clean the track.
     
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  7. rray

    rray Staff Member

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    Find the bridge and wire your supercap to the + and - output of the bridge. It's 4 discrete diodes on some decoders and a packaged bridge on others, but easy to find the outputs with a meter.
     
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  8. husafreak

    husafreak TrainBoard Member

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    • A supercapacitor (SC), also called an ultracapacitor, is a high-capacity capacitor with a capacitance value much higher than other capacitors, but with lower voltage limits, that bridges the gap between electrolytic capacitors and rechargeable batteries. Wikipedia
    • While an ordinary electrostatic capacitor may have a high maximum operating voltage, the typical maximum charge voltage of a supercapacitor lies between 2.5 and 2.7 volts. Supercapacitors are polar devices, meaning they have to be connected to the circuit the right way, just like electrolyte capacitors. eepower
    Thanks guys, I'm getting closer to a full understanding. I did much better now just searching "supercap". I have seen single cap installations in empty cars wired to the motorized car, or lights, so those were not supercaps. And now understand now why a supercap installation would require 4 caps for Z scale (4x2.7=10.8v). But couldn't the cap array just be soldered to the track power pads on the decoder? Finding the "bridge" on a DCC decoder might actually be a show stopper for me with my lack of knowledge of circuitry although I'm sure the manufacturers could point me to it. Anyway, I wonder why that point is special.
    I do have a good candidate right off the bat. A Marklin Rail car set with one powered car and interior lighting that flickers constantly in use, but it is DC and would be very simple to do. I guess my AZL Mikado would be a good candidate for DCC as it hasn't been converted yet. Assuming there is room in the boiler for the supercaps. But of course this seems like a solution for a problem loco rather than a good running one!
     
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  9. husafreak

    husafreak TrainBoard Member

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    For anyone following this discussion I was lucky to get a phone call from Jeff M and learned a lot about these caps and how they should be implemented, a lot of it made sense but a lot of it also sounded like "professional skills required, do not try this at home!". Apparently these caps will blow up if you don't treat them right... So the bottom line is if i do try to use caps in a car I will take each project separately and one at a time. Maybe I'll start with that Marklin Railcar but that's a DC lighting application and not appropriate for this thread.
     
  10. SJ Z-man

    SJ Z-man TrainBoard Member

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    LED's make the light flicker more pronounced, as they respond instantly. If track power pickup is not perfect, you will obviously see it. Without a supplemental energy source, this will continue. With the older incandescent 'grain of wheat' bulbs, this is minimized due to persistence of the internal heated wire, with lessor need for a supplemental power source. In either case, DC track runners can never have lighting while a train is stopped, without a supplemental power source.

    For a simple source, a battery can be used and with low current LED's ( <10 mA), the batteries can last a reasonable amount of time. But only the small button or AAAA batteries can fit in some locations.

    For using track power, generally a Capacitor (Condenser for the Euro folks) can be used, with some limitations and sacrifices. First, as an Voltage source, they have poor 'reserves' when Current is consumed by the LED('s) or worse, incandescant 'grain-of-wheat' bulbs. For example, using 10 Volts (lets make the math easy), and a 10 mA Current in the LED (fairly high but the nominal 'design' Current), a 10 uF (microfarad) would be off in 16 ms ! A 100 uF cap would be 160 ms. Using just 1 ma (most "white" LEDs will show much more blue) would get you 10x time for the same capacitor values. Usually, there are several LEDs so that consumes more. This is just a general discussion and in these cases, both LED and incandecent bulbs go dimmer with less voltage & current.

    As for Capictors, the classic cylinder type are huge and have less uF per size than Tantulum or Ceramic verions. All have Polarity and Over voltage sensitivity. The big cylinderical electrolytics are much saver to over voltage that you could get a away with a 12 volt rather than 16 volt spec. But for the Tantulums, definitely 16V. The Ceramic versions not so sensitive but 16 volts is safer. The Tantulums and ceramics can be stacked or side-by-side soldered to increase the Capacitance. Pointless with the large cylindical electrolytics.

    You also need to put a 10 - 100 ohm resistor between the capacitors and the track, as a fully discharged capacitor needs lots of current to charge up (but lessor as it charges and it will charge in 1-10 ms). This keeps the electronic speed controls, especially Rokuhan, from tripping 'Short'.

    Most importantaly, you MUST use a 'bridge rectifier' to convert the DC track polarity changes (or DCC's "AC") into a single polarity ! Ngineering.com sells rectifiers by themselves for you to solder or, on a micro PCB to make life easier. Look under "Lighting Accessories" on the left. Their 2 rectifiers are N301S-2 at .165" square and N302S-2 at .075 square. The micro PCB is N801S-2 at .32 x .15", quite small.

    Ngineering N301S-2 ubridge .165''.png Ngineering N302S-2 ubridge .075''.png Ngineering N801S-2 AC-DC board.png
     
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