I have been unable to sort out some odd electric gremlins on my layout. As backround, it is medium size with 4 blocks protected by an early PSX 4 and a pair of PSX AR, one for auto reverse, the other to a turntable (unconnected at this time). Operating system is an MRC Prodigy Advanced 2 and an MRC 8 amp booster. Track is Atlas code 100 with PECO Insulfrog turnouts unmodified. The layout has two blocks for a mainline half of which rises to an elevated section while the rest is at surface level. I have two yards side by side one for rolling stock, one for sercice with a turntable, roundhouse and backshop. I have busses for each section, and that seems to be where the problem arises. I have an unfindable short between the two "mainline" sections. That doesn't seem to make any difference in operations. The issue arose when I finished and hooked up the yards. Either yard is entered from the lower main line from a common throat. There the throat divides into the classification yard and the service yard. The classification side seems ok, but the service yard is giving me fits. All the tracks seem to be wired ok, the gaps are by cuts and insulating joiners both and with the power off, everything is isolated from the rest of the layout. When a locomotive enters the throat, it will stall when it enters the service yard lead. No breaker lights go on but once the whole thing shut off and reset. Sometimes throwing turnouts seems to change things but not the dead stop on yard entry. I am at a loss as to what to do short of unsoldering the drops from the buss wires one at a time. This is my third layout since I got back into this but only my first DCC setup. Any Ideas would be greatly appreciated. Thanks in advance. J.R.
Your link seems to be something on this site, perhaps the Community Photo Galleries, but we can't see it. I think we are going to need a pic.
GMTRacingSometimes throwing turnouts seems to change things but not the dead stop on yard entry.
What changes?
Henry
COB Potomac & Northern
Shenandoah Valley
Does the loco stall on turnout or on a regular stretch of track?
Maybe just do a very careful, one wire at a time, look at your bus, and feeder connections.
Yea, I know, "All the tracks all seem to be wired OK". Maybe not?
Mike.
My You Tube
GMTRacing Either yard is entered from the lower main line from a common throat. There the throat divides into the classification yard and the service yard. The classification side seems ok, but the service yard is giving me fits. All the tracks seem to be wired ok, the gaps are by cuts and insulating joiners both and with the power off, everything is isolated from the rest of the layout. When a locomotive enters the throat, it will stall when it enters the service yard lead. No breaker lights go on but once the whole thing shut off and reset. Sometimes throwing turnouts seems to change things but not the dead stop on yard entry.
Either yard is entered from the lower main line from a common throat. There the throat divides into the classification yard and the service yard. The classification side seems ok, but the service yard is giving me fits.
All the tracks seem to be wired ok, the gaps are by cuts and insulating joiners both and with the power off, everything is isolated from the rest of the layout.
When a locomotive enters the throat, it will stall when it enters the service yard lead. No breaker lights go on but once the whole thing shut off and reset.
Sometimes throwing turnouts seems to change things but not the dead stop on yard entry.
My first question relates to the PSX-AR. Where is the reversing section in all of this?
You say that the classification yard "seems OK". Is it OK or isn't it OK?
You say that a locomotive will stall when it enters the service yard lead. Will it "stall" or is it the result of a short?
You say that sometimes throwing turnouts seems to change things. "Seems to"? How so? Does the problem occur on the turnout?
We need to know more here, and you need to pin down the problem more definitively. "Seems to" is too vague and uncertain for a precise analysis of the problem.
Rich
Alton Junction
Thank you for the responses. I will do a track diagram and get that posted as soon as I can as I'm on the road for the next week.
I looked at the drops again and cannot see a fault in either main so I concentrated on the yards. The classification yard all works. Seems to work was misleading, I don't get any stalls or short lights in there at all. It is isolated from all the rest and has its own circuit on the breaker.
I found turnout position on one end of the service yard affected the locomotive running to prove the tracks. Since the PECO turnouts are power routing, throwing the points to remove power allowed the locomotive to continue up the throat but only to the gaps for the service yard. I could hear the breaker reset in the locomotive so at that point I shut everything down and went back to checking drops and continuity. I did find a simple mistake at that point as I had two entrances to the service yard from opposite sides of the loop of track around the yard. That set up a reverse polarity issue. Oddly running into the area didn't light the short LED on the PSX. Since I didn't have the PSX/AR for the turntable hooked up, I hooked the service yard to that AR and could then enter the throat from the previous place of reverse polarity . I still have something else going on and will next time recheck continuity in the power routing turnouts and recheck drops to the buss though those are fairly simple. The gaps for the service yard show no continuity so that is correct. Is there anyway to actually check polarity on the track? When I laid out the mains, I checked and proved everything one section at a time and thought it was correct. The issues seem to be around the service yard now. Thanks again for the advice. J.R.
GMTRacing The gaps for the service yard show no continuity so that is correct. Is there anyway to actually check polarity on the track?
The gaps for the service yard show no continuity so that is correct. Is there anyway to actually check polarity on the track?
One way is to watch the D6 LED on the PSX-AR board. As a locomotive enters the reversing section, the D6 LED will either begin flashing or it will go off, depending upon the order of wiring from the output side of the PSX-AR. Let's say, the D6 LED flashes as the locomotive enters the reversing section. The D6 LED will go off when the locomotive exits the reversing section. If the locomotive then stops and changes direction, the D6 LED will remain off as the locomotive re-enters the reversing section. The D6 LED will begin flashing as the locomotive exits the reversing section. That alternating LED signal, either flashing or off, indicates the status of the polarities inside and outside the reversing section.
Another way to check polarity inside a reversing section is to use a test bulb or resistored LED. Put the two legs of the bulb or LED across the gap on the same rail. If it lights, the polarities inside and outside the reversing section are mismatched. If it doesn't light, the polarities inside and outside the reversing section are matched which can be proven by putting one leg on a rail inside the reversing section and the other leg on the opposite rail outside the reversing section to produce light.
A third method is a voltmeter. Use the probes in place of the legs of the bulb or LED.
Do you have any power routing turnouts? That one fried my brain in a yard once with peocs. You would think it wouldnt matter, but beacuse the way it powers the end rails if you have additional feeders past the turnout it can create a short or a dead spot depending on your wiring
I've never played with trip currents, but I will once my layout is back up. I have a similar problem, but only the first time through. After that it's fine until the next session.
It takes an iron man to play with a toy iron horse.
Thank you all again for the help. Yes the turnouts are all power routing Insulfrog type unmodified. I have been checking things and have found besides the polarity problem at the lower yard entrance, that the yard throat turnout from the main creates a dead short, and one turnout in the middle of the yard stops everything as well. I am stymied trying to get track layout scan from my 'puter to Flickr but will continue to try to get that done before I go out on the road tomorrow morning. Thanks again, J.R.
service yard 001 by J.R. Mitchell, on Flickr" alt="service yard" />
JR I sent you a pm.
Meanwhile maybe this page will help. What the article calls "point rails" most of us call frog rails.
https://dccwiki.com/Peco_Insulfrog
Henry, I think you hit the mark with the entry throat problem. I was starting to suspect as much but didn't confirm the issue. I have the DCC tutorial saved on my 'puter but hadn't read as far as the turnouts yet. I will try to space and insulate the heel of the entry turnout frog next time I work on the layout (probably not until next week when I return from my road trip). Thanks, J.R.
Here is the layout in question. I'm on my way out the door and haven't had time to think about it.
Here is a hopefully better and more understandable drawing of the service yard. The turnout circled in black is the one that shuts everything down when thrown to the diverging track.
service yard track plan 001 by J.R. Mitchell, on Flickr" alt="service yard sketch" />
It is substantially different from the original sketch J.R.
Is the PSX-AR in the red section needed for the turntable? I'm having a hard time seeing another reversing section in tht zone.
GMTRacing Here is a hopefully better and more understandable drawing of the service yard. The turnout circled in black is the one that shuts everything down when thrown to the diverging track. service yard track plan 001 by J.R. Mitchell, on Flickr" alt="service yard sketch" /> It is substantially different from the original sketch J.R.
Where do you feel the reversing section is located and where are all of the gaps located to fully isolate the reversing section?
This is the only reversing section I see, but there maybe others. He does have 2 PSX-AR's From A to C, it looks short, but that may just be it is not to scale.
On the second drawing both A B and D are the same points as the 1st drawing. The shorted turnout is in the center of the star.
Comparing both drawings, I think the connections to the mainline are at the two tracks at the very bottom right and the yellow star on the top right side of the page.
Henry,
B in the first sketch is on the other side of the aisle. I tried to make things clearer by taking out most of the main lines and classification yard. B in the second sketch is the start of the green reversing section in the first sketch. A is the isolator between the service yard and the yard throat. D is the isolator between the the lower and elevated parts of the main. The star is in fact where the turnout shorts the yard. Just to the left of B in the second sketch is the second isolator for the service yard.
On a brighter note, thank you. The medium turnout at the entrance to the yard throat shorts out the system. I also found one other medium radius turnout that can short out and will now check all the rest of them. The turnouts i'm having trouble with are the oldest I have recycled from a previous layout. J.R.
I'm lost. Where is the reversing section in the second drawing? I am not saying that there isn't one. I just have no idea where it is situated in that second drawing.
Rich, it is just a stub on the lower right. I will when I return from my trip take my drafting kit, colored pencils and paper and do the whole track plan in a larger format and then figure out how to get it onto the forum. I am out of time for now as I have to get up and go at three this morning. Thank you for your patience. J.R.
richhotrainI'm lost.
The second drawing is just a close up of the center of the first drawing, that's why I put the letters in for reference. Try opening them up in different tabs and switch back and forth.
If the reversing section is simply a straight section of track between two turnouts, it would be isolated by gaps at both ends of that straight section of track. Simple enough. So, if the reversing section is correctly gapped, then there is a wiring problem inside the reversing section.
Rich,
I'm back but no drawing just yet. To update, the reversing section works just fine as built, it is a straight section with gaps at both ends. A large issue was the medium and large radius PECO turnouts I'm using. I was unaware they are prone to shorting across the gap of the frog and I'm correctiing that. I have one more issue I will explore after I have modified my turnouts. Hopefully I can start on the drawing tonight. Cheers, J.R.
If I recall correctly, these are Peco Code 100 Insulfrogs. Correct?
Yes that is correct. I didn't realize the wheels could bridge the gap at the start of the frog. I used the dremel to contour the middle down far enough back to stop that happening and will fill the contour with epoxy and finish the top back to flat. The alternative was to gap the turnouts just past the frog and I thought that not as good an idea. I had no idea the frogs were a problem until it was pointed out to me. Previously I had DC and no issues. The tutorial was a big help there. Any different ideas before I get the Dremel back out? We live and learn. J.R.
GMTRacing Here is a hopefully better and more understandable drawing of the service yard. The turnout circled in black is the one that shuts everything down when thrown to the diverging track.
Looking at your diagram, are the tracks above the turnout in phase with the tracks below the turnout(is the positive and ground on the same rail on all tracks) ?
I have checked the drops and buss and it all seems in order though logic dictates that they can't be if it all stops when the one turnout that connects the upper and lower yard entry is thrown. One buss feeds the whole thing and the yard is isolated from the rest of the trackage. That is the reason I have been reading the tutorial, I never knew how much I didn't know. I will try the one suggestion of using an LED with a large resistor to check polarity between the two sections of the yard. Not sure how else I can check that. Of all the issues, that now seems the most serious. J.R.
I wish that you could post a photo of the reversing section and connecting tracks.
Your most recent diagram and the one posted by Henry (Big Daddy) are dramatically different with the diagram posted by Henry showing a straight reversing section with no turnouts inside the reversing section, whereas your diagram shows any number of turnouts and connecting tracks.
It is impossible to get a sense of the overall layout, or at least the affected area.
GMTRacingI will try the one suggestion of using an LED with a large resistor to check polarity
Does that work?
Reading this thread, I would think an LED would be lit all the time
caboose lighting