Electronics and DCC

 Hi all-

It's been a LONG time since Physics 101, and I'm finding I'm having trouble getting some basic wiring up and going.  So here is what I've done so far:

 I have a point to point layout with almost all of track laid and a good number of feeder wires soldered into place.  I wanted to test my track plan operationally and start running trains around the layout.  I have a DC power pack and a non-DCC equipped loco that I was going to use for these tests.  I ran a pair of feeders from the transformer (which is located roughly in the middle of the layout) to one end and used insulated staples to hold the wire in place and screwed terminating caps on the end of the bus wires so that there was no exposed copper. 

I then (stupidly in retrospect) started connecting feeder wires to the bus wires using tap splices and had roughly 5 pairs connected.  However there was no power to the track. I assumed I had a short somewhere caused by debris on the tracks, but careful examination revealed nothing.  I then started cutting off the feeder wires one by one in an attempt to isolate the issues to a shorted wire, etc. but there was no problem.  Finally, in a moment of desperation I soldered a pair of feeder wires to the END of my bus wires and connected them to the layout.  PRESTO!  Things started working just fine (albeit I now have a bunch of shortened feeder wires that I need to reconnect to the bus wires).

Based on my (admittedly limited) knowldge of basic electricity then it shouldn't matter if I have power the wires just coming to a stub end, but things certainly seem to be pointing that way.  Also, as a test, I created a small loop of wire that I connected to two of my feeders and then connected these loops to my power pack.  Nothing reaches the tracks.  I have power coming out of the booster but still nothing reaching the track

So that comes to my question:  I plan on making this layout DCC in the near future (I have the Zephyr system, but I don't have the decoder equipped locos on hand) and my understanding is that I could simply swap out the power pack for the Zephyr at the right time, but my experiences are pointing to a different conclusion.

Any help on this would be greatly appreciated.

~rb

rfbranch:

I ran a pair of feeders from the transformer (which is located roughly in the middle of the layout) to one end and used insulated staples to hold the wire in place and screwed terminating caps on the end of the bus wires so that there was no exposed copper.

there was no power to the track. I assumed I had a short somewhere caused by debris on the tracks, but careful examination revealed nothing.

I soldered a pair of feeder wires to the END of my bus wires and connected them to the layout.  PRESTO!  Things started working just fine.

it shouldn't matter if I have power the wires just coming to a stub end

as a test, I created a small loop of wire that I connected to two of my feeders and then connected these loops to my power pack.  Nothing reaches the tracks.

I have power coming out of the booster but still nothing reaching the track

Have you tried simply connecting two wires from the DC power pack to the track and trying to run a loco? 

 Sounds like your tap connectors aren;t working right. You either have the wrong ones for your wire size (it DOES matter - big time) or you perhaps aren't installing them correctly. Strike 934829101 against tap connectors.  Get one of those good Ideal brand wire strippers (they strip in the middle of a run of wire, as well as the ends) and strip small sections of the bus and wrap the feeder around it and solder. Yes, I am a big proponent of soldering ALL connections and never relying on a crimp of any sort. Even when I attach crimp on loops at the ends of the wire to make it easier to attach to terminal strips - I crimp the terminal on, and then also solder it.

                                                         --Randy

 Hmm...thanks to you both for taking the time to reply and apologies if I ramble sometimes!  Trying to get the problem across in text is a bit tricky, but based on your comments my suspicion is incorrectly sized tap splices (aka suitcase connectors).  I'll try isolating these tonight after work to see if this is in fact the problem.  I'll report back results.

~rb

I know my solders work, and that is the only way I connect feeders to the bus.  Wrap and tin.

In another scenario this might be related to turnouts that power route, and that your turnouts were not lined for the segments of track to which you had desired power to route.  Although, it would not explain the successful end connection.  In that respect, I agree that one or more of your connectors is faulty in either design or application.

Soldering is way cheaper.

-Crandell

I think that a $10 voltmeter is a pretty inexpensive tool for figuring this stuff out.

Many people don't like suitcase connectors, I think they can work fine, but the must be installed correctly, with the right wire size, or they are not going to be satisfactory.  And by installed correctly, I don't meant the way the guy in the DCC Dream-Plan-Build video did it!  (One of the reasons I sent it back... rant off.)  The "blade" needs to be seated first, and the the cover snapped on.  Don't try to seat the blade by mashing down on the cover.

Picture of your turnouts please.

If you have power by the points routing turnouts, that's the source of your shorts 10:1.  You have to feed power from the points.

You can test this with a volt meter set to the ohm meter setting.  Turn off the power, disconnect the power pack.  Put the ohm meter on the two inner rails past the frog on the turnout.  If it reads 0 ohms, that's your problem.

If running DC you might want to recheck the wiring. Even if you did only one wire wrong it would cause problems, but make sure that you have all the right feeder wires going to the right bus wire. That wasn't very clear, what I meant was make sure that all the feeder wires for your outside rail are connected to the same bus wire, and all the feeders for your inside rail are connected to the same bus wire. Oh, and make sure they are different bus wires.

 Thanks to all for the advice.  I have a few things I can try and tackle.  I actaully have a voltmeter at home and have been using it to diagnose my issues so far (which is why I knew it wasn't an issue with the transformer). 

 On my turnouts I have "DCC friendly" Atlas Customline C83 #4's and a set of four Peco #5's so I don't think it's an issue with power routing turnouts (especially since I seem to hve power with just a simple soldering of wires).

I'm starting to think the issue is the tap splices, but I can't get over that not a single feeder connected properly on my entire layout.  Just seems to boggle the mind (not that I don't believe it, but it's just amazing).

I'm stopping at Radio shack on the way home from work tonight and I'm picking up some terminal strips and connectors so that i can wire the layout up without the tap splices.

I'll report back if I still have issues, but the more I think the more I think that is the likely culprit.

~rb

 I'm suspecting the difference between working and not working lies in the solder, not in the position to which the connection is made (end vs somewhere in the middle).  Sounds like maybe your insulation displacement connectors aren't making contact.   

    Converting to DCC is merely the replacement of the DC power pack with a DCC control box or booster.  If the wiring works for DC it will work for DCC.  

 I had problems with suitcase style connecters in the old automotive days   They worked great for awhile then lost connection  Although that may be due too weather/ temperture/ humidity of the air in a car