Atlas Turntable Motor - Voltage Issue

Discussion in 'HO Scale Model Trains' started by 42XExpress, Sep 18, 2006.

  1. 42XExpress

    42XExpress New Member

    Hey everyone - I've been lurking for quite awhile now and have really enjoyed reading everyones posts and replies about questions and layout progress. Really a great resource. I've done some searching and I didn't find a post about this so forgive me if this has already been answered.

    I finally got back into model railroading after a 10 year break and am in the process of building a 100 sq ft layout in the wet bar area of my basement. (Its amazing what you can do when you're a 27 yr old single adult with your own house, a good job, and a girlfriend who brow beats you about what a nerd you are)

    ANYWAY, I've almost completed the freight yard section of my layout which conists of an 8X4 ft section. I bought the atlas turntable and motor and am really happy with the turntable, but am having troubles getting the atlas motor to turn the gears. When I run the motor manually with my hand it works great. When I hook it up to an old Tyco powerpack with 18V of output, it will run, but it runs too fast and the spindle thingie doesn't turn the gears. Atlas recommends a 12V power supply. All the accessory powerpacks I find are 18V or somewhere around there. What does everyone recommend to get 12V of power to the motor? Or am I going about this the wrong way?

    I'll submit some pictures soon!

  2. shaygetz

    shaygetz Active Member

    Welcome to The Gauge:wave:

    A 12 volt "wall wort" type transformer, the kind you get as an AC adapter for computer speakers and such will do the trick just fine. I bench test mine with a good 9 volt battery and even that works well enough.
  3. stuart_canada

    stuart_canada Member

    i would get rid of the tyco power pack and get a newer one.
    the newer power pack will have the right voltage to run it and provide you with better power
  4. hooknlad

    hooknlad Member

    Question regarding the question: Couldn't you utilize a 12 volt variable DC transformer to feed the turntable so that the turntable will not make an annoying "motor" noise and that it will travel at a relatively slow speed? Just my $0.02 .
  5. FiatFan

    FiatFan Member

    That's what I did and it works quite well.

  6. Nomad

    Nomad Active Member

    I have the atlas turntable also. The turntable motor should be wired to the same treminals that supply track voltage. That way you can control the speed and or direction of rotation.
    I use a old starter pack that came with a train set. All i use it for is the turntable and the ac voltage for building lights. Hope this helps.
  7. hooknlad

    hooknlad Member

    I have to be perfectly honest here - The only thing i use the ac terminals for is for the switched turnouts.. The lighting in the houses are also on variable dc ( differnt xfmr) so that i can dim them as well and they will last longer.
  8. doctorwayne

    doctorwayne Active Member

    It looks like you've got the answer to your question, so I'll simply tell you of an incident that I witnessed, quite a few years ago, involving a real turntable. As modellers, we expect our turntables to move slowly, which helps to convey an image of heavy, ponderous machinery, and also makes it easier to line things up with the proper track. I was at the TH&B's Chatham St. roundhouse, in Hamilton Ontario, taking a few pictures. The hostler brought a GP-7 out of a stall, onto the turntable. I was about 200' away when this occurred, and wasn't bold enough to leave the parking area (which offered a good view of the fuelling and sanding facilities) or to speak to people doing their jobs, so I never did get an explanation of what happened next. The turntable accelerated rapidly, spinning the loco around like a toy, so much so that when it stopped, the Geep was rocking on its springs, from side-to-side. I don't know if there was a malfunction, or if somebody had souped-up the thing in an effort to speed up the task, but I wouldn't have believed it had I not seen it with my own eyes. Another example of there being a prototype for everything, I guess.:) The hostler seemed unfazed by the incident, taking the locomotive away to another shop building, as if nothing unusual had occurred.
    My own turntable, scratchbuilt, is an "energy efficient" model, powered by a device related to the 0-5-0 switcher: a giant finger. :D Its speed depends on the enthusiasm of the operator.


  9. prof100

    prof100 New Member

    Hi will a dimmer switch wired into the motor work also.

  10. Oh, you're funny. sign1

    Hrm...I do believe that what grewsome said is probably the best idea; wire the turntable to the power pack through an Atlas Controller. That will allow you to control not only the direction, but the speed and even the time it takes to come to a full stop (realism buffs love that).
  11. Russ Bellinis

    Russ Bellinis Active Member

    Just one word of explanation for you. When you look at the spec tag on a ho or n scale power pack, it doesn't say "18v". It says "18va". I'm not sure of the exact meaning, but it has to do with a combination of volts & amps. The higher you turn the voltage the less amperage you have available and the lower the voltage, the more current is available.
  12. pgandw

    pgandw Active Member

    Could be way off on this one - don't have any reference material or an Atlas turntable motorizng kit at hand.

    I believe the motor runs off DC only - just like your locomotives. Hooking it up to the AC accessory terminals of the power pack will eventually overheat and let the magic smoke out of the motor. When operated on AC, the motor will buzz and not do anything before it gives up and releases the smoke.

    Operating the turntable through the Atlas Controller is certainly a valid method. This takes care of the polarity reversals, direction switches, and turntable direction in one unit (your turntable is a reversing section/loop). Your control on your DC throttle controls the speed of the turntable. Atlas layout wiring diagrams show how to wire their turntable.

    my thoughts, your choices
  13. hooknlad

    hooknlad Member

    prof100 - i believe an electronic dimmer ( the kind that you use for light dimmer for a chandelier ) will not work.. The dimmer utilizes some simply electronics that require a preset voltage and wattage... Therefore a simple ac turntable wont be able to be controlled by a dimmer. the turnatbles voltage and wattage are way too low to be small ( negligable) to even trigger the SCR circuit in the dimmer. Hope that helps and BTW, Welcome to THE GAUGE !!!
  14. stuart_canada

    stuart_canada Member

    i learned from a mistake, the motor is for dc voltage only, i hooked mine up to the wrong side and almost burned it out.
    get a atlas control for the turn table and it will work better i am sure

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