Hoping for some expert advice that points right to a problem. I have just started a DCC layout and am working on the staging yards and helix. I have run a pair of 14 gauge wires from the command station to separate power blocks (grey and black wires for consistency) where there are 8 pairs of 20 gauge wires running up to roughly 4' sections of track. When power is applied, the track power light on my command station flashes and the loco will not run. I double, triple, quadruple checked all the wiring to ensure nothing is wired to the opposing rail. I then disconneced the track power from the command station and used a different pair of wires and ran to a section of stand-alone flex track. Powered it up and all worked fine. I checked wiring again and re-connected the command station to the track and received the blinking red light again. I am running atlas custom line code 80 and a few Kato insulfrog switches. Neither should need special attention with DCC. Total track lenth is around 30' (double tracked). Anybody have some advice on simple things to look at? I know this is a simple issue I am just missing.
Can you post a track diagram?
Does the staging yard loop around on itself? Is there a wye formed? Either of those cases will require an autoreverser to match the polarity. It's definitely crossed somewhere, or you wouldn't get a dead short.
If you have a multimeter, set it to continuity mode (especially if it has a beep mode) and connect it to the bus in place of the DCC system, it will indicate a short and beep, if you start trying to track things down, it will stop beeping and show open when you have it fixed.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Code 80 means N sale and whatever DCC system I'm going to guess a flashing light and no movement means a short
Congrats I think you told us most of what we need for someone to figure it out. That may not be me.
If the system works on an isolated piece of track, then the system works. Atlas turnouts are not power routing so that is not the problem
Kato, I'm skating on thin ice. I recall that some Kato can be adjusted to be power routing. I don't know if that is insulfrog, but someone will know. If they are you would need insulating joiners on the frog rails.
Even though you quadruple checked, when working underneath the layout, mistakes happen. You have separate blocks. Start disconnecting in a logical manner so you can test one block at a time.
I think you are right, it is simple and you are looking at the problem but can't see it.
Henry
COB Potomac & Northern
Shenandoah Valley
If you have power-routing turnouts on either end of a siding, and if the turnout on one end is lined to take the siding, but the opposite turnout is not, you'll have a conflict in routing...a short. That is why it is a good idea, in a yard especially, to gap the end of one of the two turnouts. Leave the powering of the rails between the two turnouts to only one of them. That way, if you make a mistake and only line of the two turnouts correctly, you won't get the short. Of course, you'll still get the short if you run metal tires over the gap and one of the turnouts is in the wrong setting.
I thought about what I left off after I went to bed. No wye or reversing loop in the design. I have aligned all switches to the main as a thought as well. I have power on either side of all switches for the purpose of ensuring down the road my trains do not hesitate or have problems on yard tracks. I will try the multi-meter approach suggested here... if that does not work, Saturday may be a long day of testing section by section until I find and isolate the problem.
jpdriver I have run a pair of 14 gauge wires from the command station to separate power blocks (grey and black wires for consistency) where there are 8 pairs of 20 gauge wires running up to roughly 4' sections of track. When power is applied, the track power light on my command station flashes and the loco will not run.
I have run a pair of 14 gauge wires from the command station to separate power blocks (grey and black wires for consistency) where there are 8 pairs of 20 gauge wires running up to roughly 4' sections of track. When power is applied, the track power light on my command station flashes and the loco will not run.
Randy has asked for a track plan which would definitely help. So would a more detailed explanation of your wiring protocol.
Rich
Alton Junction
You're going to have to isolate things - if you hook the meter on now, it WILL indicate a short between the two rails, since your DCC system already indicates the same.
If you have terminal strips along the bus that you can break it into two pieces without cutting the wires, that would be the palce to start. One side may have the short, the other not, thus you have reduced the area you need to look in detail at to just the half showing a short.
You didn;t leave a metal tool laying across the rails, did you? That's easy to overlook.
In thinking about this issue, I keep going back to the term "power blocks". This may well be a wiring issue. If it were simply one undivided layout (no gaps) with feeders from the single pair of bus wires, it would be easier to find the short. But, it would appear that the issue is not that simple in this case.
Since the system works with just two wires to a piece of flex track, is it possible to UNINSTALL your layout wiring by sections, thereby isolating each section and testing them idividually to see where more specifically the problem is? You would test it each time to see what section is causing the short.
I'm sure you're trying to avoid undoing any wiring that is ultimatley ok, but narrowing down a large layout into smaller chunks seems like it might be faster.
- Douglas
Definitely ensured the rails were clear of obstacles. I plan to disconnect the bus from the track power at the terminal blocks (2 at this point) and verify the bus is operating through the blocks correctly and independently. The helix is isolated from the staging yard due to Micro Engineering plastic transition connecters (code 55 to code 80). I can definitely test the helix with the yard isolated off the bus without a ton of work. In researching the Kato insulfrogs, I am wondering about a potential for a broken wire under a switch at the frog coming into contact with the other pole. I may find myself removing a few sections of track to keep from undoing a lot of solder joints to the rails. Supposed to snow Saturday, so a good day to stay in and spend some quality time on this. I will let you know what I eventually find out.
As on add...my Digitrax Command Station was out for service with the manufacturer for the last month as I worked on this part of the new layout. Otherwise I would have powered up the very first section constructed...not by choice that I ended up just now powering up 40' worth of rail.
OK, this is good follow-up info.
So, you are running the primary bus wires from the command station to two terminal blocks. The helix is isolated from the main layout and isolated from the staging yard. Is the staging yard isolated from the rest of the layout?
I cannot speak to the Kato Insulfrogs, but before you start desoldering rail joints, test the terminal block connections. What is your wiring arrangement from the command station to the terminal blocks? Are you running one bus wire to each terminal block?
P.S. A track plan would be helpful.
jpdriver I may find myself removing a few sections of track to keep from undoing a lot of solder joints to the rails.
I may find myself removing a few sections of track to keep from undoing a lot of solder joints to the rails.
That's probably an easier way to do it in many places.
This should be a lesson for everyone. DO NOT build and solder a lot of trackwork without stopping and testing occasionally. As long as it keeps working, fine, but as soon as you get a short, you must stop and correct it before proceeding.
With a step-by-step approach, the last thing you did before getting a short is the problem.
It takes an iron man to play with a toy iron horse.
MisterBeasley This should be a lesson for everyone. DO NOT build and solder a lot of trackwork without stopping and testing occasionally. As long as it keeps working, fine, but as soon as you get a short, you must stop and correct it before proceeding. With a step-by-step approach, the last thing you did before getting a short is the problem.
Very good advice! And testing doesn't have to mean powering up, just use an ohmeter to make sure you have no shorts. Power up now and then to check for other sorts of faults, and to ensure you have good connections.
Found the problem. Brand new code 80 Atlas custom line switch is faulty. It has a manufacturing defect visible in the frog. Dead center in the plastic frog is exposed metal about the size of a pebble. Not sure if this is the actual problem but it is indicative that the metal is not where it should be. The switch was isolated and eventually tested separate from all other switches. Once removed, everything was fine on the layout. Who would have guessed a DCC friendly out of the box switch would be defective.
That's like the third defective Atlas turnout recently - although first N scale I think. What the heck is going on here...