Newbie question about wiring

Discussion in 'FAQs' started by Insey, Mar 28, 2005.

  1. Insey

    Insey Member

    The transformer on my HO set shut down the other day as soon as I plugged it in (after not being used for months). I got my volt meter out and tried to find where the short was. I tested each building/street light individually. To my surprise, what I found was about half of all the lights made my volt meter beep (meaning the two leads from each light were crossed somewhere). Is this normal? Or does it mean the lights need to be replaced? Thanks in advance.
  2. ezdays

    ezdays Out AZ way

    I'm assuming that you are using your meter as a contiunity checker and will beep on a short. Most lamps when not lit have a very low resistance and will show up as a short or near short. That's normal

    What I'd do is to disconnect the power pack from the layout and turn it on. Measure the voltage to see if it is high enough. Take one lightbulb and put it across the output and see if it lights. This will test the power pack for you.

    Finding a short using a continuity tester this way is difficult, so you may have to disconnect your wiring at the halfway point and reconnect the power pack to the layout again. If it works, the problem is in the second half, it doesn't, the problem is in the half still connected. Keep isolating this way untill you find the problem.

    :et us know how you're doing.
  3. Insey

    Insey Member

    Ok thanks. I am going to try that right now.

    By the way, would a short in my train board cause half my basement to lose power?
  4. ezdays

    ezdays Out AZ way

    I would tend to say no, unless you were running the rail voltage directly from the wall socket. :eek::cry: Your layout is run from the output of a transformer and is isolated from the main house power by that tramsformer. The transformer would get very hot and burn up first, but most power packs have some sort of protection. Either a circuit breaker (or fuse) or some sort of thermal cut-off switch that disconnects the AC input if the transformer or power pack gets too hot.

    Keep us posted.
  5. Insey

    Insey Member

    Eh...I better get a new transformer then. One time when I turned it on, it restarted my computer from across the room. The next day the power company knocked on my door saying the neighbors are having problems with their power.

    My soldering tip just broke so right now I gotta head over to Radioshack and get a new one. By the way, is that Cold Heat soldering gun any good?
  6. Insey

    Insey Member

    One more thing, does it matter which polarity (negative or positive) of the light goes to my main bus?
  7. ezdays

    ezdays Out AZ way

    1. The transformer should be inside your power pack. I'd head over to a hobby shop or train store and look for a new power pack.

    2. I don't have a "cold" soldering iron, but from comments here and a review I read in a computer magazine, they're worth the $20 sales price.

    3. Polarity doens't matter on incandecent lamps, but it does if you're using LED's or there was some other blocking diode in series with it.
  8. Insey

    Insey Member

    Ok thanks for all your help. I think I will pick up one of those cold soldering irons in addition to the one I have now.
  9. Insey

    Insey Member

    Edit: nevermind
  10. nachoman

    nachoman Guest

    1) there is absolutely no reason why your house power should ever affect your neighbors' house. They are seperate circuits.

    2) I would think that the overload protection in your power pack would protect your house wiring, provided the problem is on the track side. If the short was in the wall side (in the cord or in the primary coil of your transformer) it should blow a fuse or circuit breaker in your house, or generate excessive heat or fire.

    3) One more thing to test - try your power pack from another outlet. There could be something wrong with your house wiring, in which a loose connection or short inside the outlet is causing arcing.

    In any event, this sounds like a problem to not take lightly.

  11. Insey

    Insey Member

    Thanks again for your help. I really appreciate all this.

    My neighbor's house and my house are "tied together", according to the electric company. I am afraid of risking another power problem again so the next time I fire this thing up, I am going to hook it up to a deep cell battery instead with either an inverter to go to the powerpack or just a bunch of resistors to go to the main bus.

    By the way, is it possible that a short exists in the light bulb itself? If so, how would I ever know which bulb it was?
  12. Connor

    Connor Member

    A light bulb IS is Short! It's basicly a small wire between 2 posts that glows red/yellow when enought power is added. They're put in a vacum to keep the wire from burning in-to.
  13. Insey

    Insey Member

    lol that basically means then that this short has something to do with my wiring?
  14. Connor

    Connor Member

    Most likely, Take out all the bulbs and check for a short again..

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