Shorted

Yesterday’s exciting progress on the layout was marred by a glitch.  I turned off the DC power pack to take care of some other things around the house.  When I went back to the layout later, it was shorted out.  I have no idea how that can happen, but I guess I’ll have to figure it out. The joys of building a home layout.

Suggestions are welcome!

Advertisements

8 thoughts on “Shorted

  1. Gaps closing are the usual culprit. Spikes can also almost touch under the ties by two rails near a frog and with wood contracting, etc, eventually touch and short out. Bare strands of wire under the layout can sometimes do naughty things as well. You might also want to go over your PC ties and see if a burr of metal shifted and closed the gap there. With DCC some of these things disappear in a wisp of vapourized metal, but with DC there’s not enough current to heat things up that much.

  2. Wish I could help. The only suggestions I have are to
    1) divide and conquer. Split the layout in half and half again etc to isolate where the short is occuring. Of course, there may be more than one…
    2) use a multimeter or even a DCC system (which is much more sensitive to shorts) to determine where the shorts are.

    • Here’s a breakdown of how I’ve been trying to solve this:
      – Checked that all of the frogs are isolated (previously done).
      – Checked all of the pc board ties to ensure that there are no burrs and that the gaps are all in the right places.
      – Checked every feeder to make sure that each one was correctly coloured when I installed them.
      – Checked to ensure that every feeder connects to the correctly coloured bus wire.
      – Vacuumed the layout to suck up any whiskers of stranded wire.
      – Checked all of the feeders and bus wires to ensure the insulation is intact everywhere.
      – Checked that the polarity of the feeders to the Blue Point terminals are soldered to the correct terminals.

      Still stumped 😦

  3. A thought occurred to me as I was checking the layout.

    I pre-wired all of the turnout controls before installing them, and as a result, some of them were wired backwards. I had to remove the leads from the terminals and I did this with the turnout controls in place. It’s possible that I may have had the heat on one of the terminals for too long. Is it possible that the contacts inside of one of my Blue Point turnout controls came loose and is now shorting out the terminals? It may have been OK for the first few times I threw the switch, but then worked itself loose after a few throws. Has anyone heard of excess heat causing issues with the guts of a DPDT switch?

  4. I found it. Two spikes that were back to back on the first tie outside of a frog gap had somehow moved enough to short out. How they weren’t shorting the layout the first time I ran it, I’ll never know. I ran every inch of the layout again, and had no problems aside from some flux and paint on the railhead in a few places. Jurgen, it was your suggestion about spikes that prompted me to look more closely at the the frogs. Thanks for that.

    This highlights another benefit of the Fast Tracks system: there are no spikes on the turnout if you use the whole system.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s