Power for ancillary items on DCC layout?

Discussion in 'Track Planning' started by Hammerli, Dec 18, 2005.

  1. Hammerli

    Hammerli Member

    I'll be running my new layout via DCC, but how should I provide power to items such as lighting, turntable and other things that don't require DCC? I assume it would be best to not have them draw amperage from the DCC power supply, but since I have no compatible power supplies coming from Z gauge I can purchase whatever would be best.

    I'd thought about buying one of the Tech4 train controls so that I could use it for something around a Christmas Tree and use it for a testing track for things I'm accumulating for the layout. Would that be a smart choice for something to use as a power supply for the non-DCC items on the layout?
  2. pgandw

    pgandw Active Member

    You mentioned several uses for a power supply, each of which does better with certain features.

    Around the Christmas tree needs are fairly simple - don't need momentum, braking, meters, etc.

    For a DC test track, I find meters and a non-pulse power supply are quite helpful. A DC test track will NOT serve as a programming track for DCC unless you install a fool-proof way to switch the test track to DCC. My test track is for tuning locomotives and breaking them in - and for that DC is better than DCC. But I do the tuning and break-in before adding the decoder - which I confess I actually never do because I don't use DCC yet.

    For accessories: Tortoise (and other stall motor type) switch machines and the turntable motor generally require DC. Twin coil switch machines and lights can use either DC or AC. The current draw of your turntable motor, and the amount of lights will drive your power requirements, but you'll need at least 12VA in reserve to "snap" twin coil switch machines, even though it's only a momentary load.

    Bottom line is that the advanced features (momentum, braking) of the more powerful Tech 2, 3, 4s don't do much for you in your particular uses. If your power requirements fit within the specs of a Tech 2, 3, or 4, then it's a reasonable solution. Probably a better possiblity is 2 separate solutions - each tailored to it's use. A low end Tech 2, 3, or 4 (used Tech 2 or 3 is as good as a new Tech 4) is fine for around the Christmas tree, and if equipped with meters, great for the test track. The easiest and cheapest solution for a moderate-to-large-sized accessory load is a suitable toy train transformer with a full wave rectifier added to provide DC where required. With the addition of meters, the transformer/rectifier setup will also work for the test track, but would not look pretty enough for most Christmas trees.

    Hope this helps.

    yours in transforming
  3. Hammerli

    Hammerli Member

    I've found a used Tech 3 9500 that has meters, and should provide more than enough current for the accessories I plan to run off of it. I'll be running the turnouts DCC, so really the LED lights and turntable won't add up to that much draw. It looks like the 9500 with the built in meters would be adequate for a test track while I am buying things prelayout, and later I can keep it on a test bench. My NCE DCC has dedicated provision for a programming track so I believe I'm set there.
  4. pgandw

    pgandw Active Member

    Sounds like a great plan to me. :)

    The turntable motor should be the equivalent of one locomotive. LEDs are almost negligible - it takes 50 of them to get to 1 amp current draw. My concerns were based on running twin coil switch machines and regular 12-14 miniature light bulbs - and I didn't know how big your layout was.

    Have fun!
  5. Russ Bellinis

    Russ Bellinis Active Member

    If I remember correctly, when the club was looking at dcc, one of the features that was a plus for the NEC system was that it doesn't need a dedicated programming track. The "hammer head" walk around throttle will program on any track.
  6. Hammerli

    Hammerli Member

    I am not fully up to speed on all of the criteria of the NCE, but according to what I recall reading in one of the manuals, what you say is true to a point. NCE says that "main line programming" can be done if the decoder is a NCE decoder. I don't know which, if any, other brands also support that feature. I figure I'm safest to just have an end of a siding on a DPDT off the dedicated programming outputs of the NCE so it can be used as a programming track but can also be switched for general use.
  7. Hammerli

    Hammerli Member

    I'm planning to use tortoise machines I believe, but my understanding was that they would be tied into the DCC supply for packet purposes. The layout is roughly 15' x 13', and there will be one 130' Walthers turntable, and about 25 to 30 turnouts. Any lighting I plan to design as LED, or convert to LED if the kit comes with light standard. My reason for doing that was just as you said, low draw, as well as longevity and temperature. I currently have the 5 amp NCE, but I can easily go to the 10 if required. Since I foresee a maximum of three, and normally two, locomotives running simultaneously, I didn't think the switches would require anything more since I'd be activating one at a time.
  8. Russ Bellinis

    Russ Bellinis Active Member

    I'm not sure, but I don't think the brand of decoder has anything to do with the programming. It is the rest of the system that does the programming, and the decoder in the locomotive doesn't know whether it is on a programming track or not, it just gets told what its program is and responds accordingly. We ended up buying the easydcc system, and when we program a decoder, the program stays in the decoder even though the club's dcc guru dumps all of the information out of the master after each show.
  9. Hammerli

    Hammerli Member

    Like I said, I've not read through everything yet, but this passage from page 17 of the NCE System Reference Manual disagrees with what you are saying.

    "When using the programming track, the remainder of the layout is stopped. With NCE decoders,all parameters can be changed on the mainline, using the “Programming on the Main” feature,without shutting down the whole layout. Many other manufacturer’s decoders do not support programming on the Main” so a programming track is required. Some owners have setup their shop loop to be DC, DCC, and programming track, then they can do all the testing in their shop and have only ready-to-run loco’s on the layout."

    What that seems to say is that the "Programming on the Main" IS decoder dependent.
  10. Russ Bellinis

    Russ Bellinis Active Member

    Actually what it is saying is that with NCE decoders, you can program on the mainline without stopping the mainline operations. With other brand decoders, you may have to shut down mainline operations to program. If you program all of your locomotives before you start operating, it will make the entire mainline a programming track if necessary. The reason I mention this is that all decoders that meet NMRA specs will work in any engine, but some won't fit physically in certain locomotives.
  11. sumpter250

    sumpter250 multiscale modelbuilder

    I have a box (panel with dpdt switches) that lets me use my test track for DC, Digitrax DCC,or Northcoast DCC. I can also select Digitrax "program track", in Digitrax DCC, or NCE "program track" in Northcoast.

    Programming on the main, or Ops mode programming, is becoming the preferred programming mode with sound decoders, as they draw too much current for the "programming track". The decoder, the base system, and the handheld throttle all have to be supportive of ops mode programming. When they are, it works just fine.
    It's all part of the DCC learning curve. ( no there are no elevators to ease the ascent of the learning curve. :D :D )
  12. kchronister

    kchronister Member

    Leaving programming track issues aside and returning to the original question:

    I run an "accessory bus" set of wires around the layout, along with my "DCC bus" wires. I tap into this circuit as needed to power lights, accessories, etc - basically the same idea as plugging an appliance into a circuit in your home.

    It's powered by a 12v DC transformer I bought at radio shack (i.e. not a train controller, just a straight up transformer). As noted before, unless you have some kind of massive or unusual accessory load, you're not talking about a lot of power being drawn...
  13. Gary Pfeil

    Gary Pfeil Active Member

    I think NCE's statement may have been aimed at some of the earlier decoders, Digitrax had a similar statement with the original Chief, with the DT100 throttle. I may be wrong but I think all decoders made in the last year or two can be programmed on the main. Many of the 4 or 5 year old ones cannot.

    I wasn't aware that with NCE you need to shut down the layout to use a programming track. That isn't the case with Digitrax, at least with the Chief.
  14. Harold Cole

    Harold Cole Member

    I would run an AUX power supply for lights and accessories,just my 2 cents.
  15. Harold Cole

    Harold Cole Member

    I'am using all Digitrax Decoders and some are more than 10 years old.All can be programed on the Main track in ops mode except you can't change the address.

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