I attached feeders to the buss lines on the layout over the weekend. I only have about a 4' section of layout wired to the buss that includes the Main, Run-Around & a spur (this includes three turnouts). I wanted to test at this point before proceeding so I can move along isolating and fixing problems as I go. Of course, I spent yesterday morning and this morning before heading to work looking in that small area for a short. I plugged my NCE PowerCab in and it started doing the electrical short sequence. I traced every wire from PowerCab to buss to feeder to rail, all is good. Nothing crossed, backwards. I even pulled up a couple spikes that had close clearance between the closure rails. I unplugged the layout from the PowerCab and it started up just fine, red light on the panel, as well. As soon as I plug the busses in, back to the short sequence. All cars off layout, (even the unconnected feeder areas) and all tools confirmed were of any rails. Still doing electric short sequence. I'm going to get a volt meter and test everything next weekend. Any ideas? *sigh*, something to dread for next weekend
GP, You did not mention what brand of track and turnouts, is it possible that some of the turnouts need insulating joiners ? Carl PS: a diagram of the track and future track may help someone else come up with the answer.
Handlaid Code 83 and 70 Micro Engineering Rail on Central Valley tie strips. Turnouts are all Shinohara #6 (insulated frogs). The Following drawing is an old XTrackCAD drawing that I added color to and uploaded to RI. I'm not on my home computer, so all I can do is "download the upload" and modify it. The bright blue box is the current area that is connected to buss line. There are rail joiners in place that could carry current to adjacent rails. All rails have been laid (except for open area in the "Old yard" area for future development) Overlook the color of each track as that isn't pertinent to the issue at hand.
Pat, very nice drawing. Since it is hand laid rail, something I have never done myself, it sort of takes it out of my wheelhouse. Having said that and the fact that you stated the adjacent rails are connected to the "blue box" rails, I am not sure your short is in the blue box. I understand that the color coding is not pertinent but look at the green line. I see two crossovers in that line with one just to the right of the box and the other in the staging yard. Again, I have never messed with Shinohara so I am not familiar with them at all. My next question would be, is it necessary to insulate one or both of the rails in the actual crossover and if so did you do that. Sounds like you are pretty savvy on this but sometimes we forget to do what is required, I am not doubting your ability, in any way, but rather trying to learn for future use or teaching new guys in our club. Carl
It's a little late for this advice, but when I wire a layout (or a piece of one) I have a little device that consists of a 9V battery, a piezo electric buzzer, and two alligator clips. This is wired up so it buzzes when the clips are touched together. I got this idea from Allan Gartner's Wiring for DCC web page. I connect this device to the buss wires. As I'm working, it lets me know if something is wrong as soon as a wire touches something it shouldn't. As far as using this on an existing layout that is already wired, you could hook this up at one end and then start disconnecting feeders until it turns off. Another alternative, which was in the November, 2013, MRH, is to put a resistor (or tail light bulbs) into the output of your power supply. You can then use a clamp-on AC ammeter to find the feeder where the current is flowing. This is a bit more expensive than the buzzer, but you don't need to start cutting wires.
I had forgotten about insulating cross overs. In my mind, if the frogs are completely insulated, then insulating crossovers wouldn't be neccesary? There is only one turnout on the layout that did originally have an insulated frog, the first curved turnout to the immediate right of the box (leads to the A&P Warehouse). I took care of that with a Dremel months ago.
Almost forgot, the crossover on the left side is handlaid from a pair of Central Valley swtch kits. The frogs are plastic, thereby insulated.
Problem Solved! Inside the "blue box", the upper left turnout leading to the shared spur with LC&C Co. & the rolling mill was the culprit. This was a Shinohara #6 R turnout that was missing the frog, closure rails and points. I rebuilt the Shinohara partial with old ME turnout parts. The ME points are joined with a soldered metal throw bar, so when I initially installed them with Walthers rail joiners, that caused the sort. Should work well with insulated joiners. I was out of town with work all week, I found the problem probably 2 minutes after I got home. Sometimes you just have to step away for a couple days.
Wired up more feeders to Buss yesterday and this morning. Shorting out again! Traced everything back once again, everything looks good. All points insulated from closure rails, frogs also insulated. A couple pairs feeders shared same hole doe to clearances, I even cut and removed them to make sure there weren't contacting each other. I have insulated joiners on the way, going to divide the layout into at least a couple sections, electrically. Should have know I'd have problems with all of these turnouts...
I would suggest that set all turnout to 'closed' (thru traffic) and if there is no short, throw them 1 by 1 until the short appears. If there is a short with them all 'closed', throw them 1 by 1 until the short disappears. Is the handlaid track soldered to any ties? If so, are all of the ties 'gapped'?
Found the problem... Again. Two of my Shinohara turnouts appear to have points separated from the closure rails. It didn't occur to me that there is a metal contact strip under neath that joins closure and point rails. Cut the copper contacts and removed from points. Everything running again. The two hand laid turnouts are on plastic tie strips spiked into plywood roadbed. They shouldn't cause any issues.
