Need some help here, I can't find the short.
I'm trying to wire a reverse loop. Some background. There are no shorts on the mainline or either yard. There is no short with the Dual frog Juicer (AR) connected to the main bus wires. There is no short with the red wire from the reverse loop connected to the AR. When I connect the black wire the mainline EB1 trips after about 2 seconds.
This is the layout wiring diagram. Neither reverse loop is wired yet.
This is the loop I'm trying to wire. The short occurs when the second rail of the reverse loop is connected to the AR.
I checked that the gaps are there and clean and that nothing is on the track. at least not that I can see.
Any Ideas?
Gary
You've got too many gaps in that loop. Remove the gaps where it comes off the main at the top left. Remove the gaps on that side of the frog of the turnout at the bottom center. Keep the gaps on the other side of the turnout to isolate the ferry district. Put new gaps ont he point side of that turnout where you have the feeders at the bottom center. From there around to the turnout at the top right center, that's your reversing section, and shoould be powered only from the output of the Frog Juicer.
And don;t forget the jumper has to be on the Pair Outputs pins on the DFJ for it to work as an auto reverser.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Randy are you describing a better system of gaps that is unrelated to his short.
and that the problem likely results from one of the following?
rrinkerand shoould be powered only from the output of the Frog Juicer. And don;t forget the jumper has to be on the Pair Outputs pins on the DFJ for it to work as an auto reverser.
Henry
COB Potomac & Northern
Shenandoah Valley
Both. That gaps in the bottom picture are not the same as the ones shown in the top picture - the top picture, it would almost surely be the way it's gapped. With one less set of gaps, it's acceptable, but my change would I think make more sense.
I'm getting crosseyed looking at the sketches.
The bottom sketch doesn't seem to match the top because the upper right end of the reversing loop (shaded red in sketch) does not originate on the same track where the far left end of the loop ends.
The yellow double mainline seems to cross itself at the figure eight crossing . . . I'll have to ponder this some more.
Robert
LINK to SNSR Blog
I don't know if I can follow Randy's method but, I'll try. What is causing the short now?
The bottom picture has one less gap than the top down by the ferry yard switch because I didn't think I needed it do I filled it in.
The bottom sketch is intended just to show the reverse loop and where it connects to the main.
The layout sketch is accurate showing a double mainline with this loop coming off the top or outside main in the upper right of the drawing and then returns to the Main on the inside or bottom loop In the center of the drawing.
Robert you're correct the bottom drawing appears to be one mainline. The top one is actual exce3pt for one gap filled in down by the ferry switch.
Hey Gary-
I'm still chewing on this.
It looks like the two gaps shown on the bottom sketch don't relate to each other. It looks like one gap is merely a gap in one of the yellow mainlines that closes back on itself, and the other gap is a gap in the other yellow mainline that also closes back on itself.
It seems like when the reverser reverses current, it can't because the main bus also connects into the same mainline.
A new sketch that eliminates the red ferry yard and the green ladder yard as well as the yellow passing siding might help. They don't play into any reversing scenario. Then, stretch out the double mainline and don't show the figure eight crossing. Also, that 'crossover' that goes toward the upper left doesn't seem to function as a crossover; more like a parallel siding.
I'm still trying to get a handle on this.
Yes, I can see that the drawings are confusing. The top one is correct except that the one gap by the ferry switch has been removed.
Randy,
Is this what you're talking about?
The jumper is on to make the Juicer an Auto reverser and the trip voltage is set to 2 while the EB1's are at 3.5.
What's causing the short?
No, you took out the wrong gap and left in the one I suggest taking out. Keep the one you marked "remove gap" in the upper right. Add the one you marked "add gap". Remove the one in the left middle where it just says "gap"
The reason being, that reverse loop is long enough that a train could be crossing the gap at the upper right at the same time a train is exiting to the ferry district and that could cause conflicting shorts that no amount of reversing the loop track polarity can fix. Moving the gaps as I suggest makes the part that goes diagonal across the middle part of the main line and still leaves a reversing section that should be plenty long - unless of course this is just a schematic representation of the layout and the track from the point side of the ferry switch back to the main around the right side is actually just a short stretch of track.
When dooes it short? Just turning on power? If it does that, you have a feeder crossed up somewhere - one from the main or ferry section on the reverse loop side of the gaps, or you have gaps that have closed up. Or does it only short when a train crosses the gaps into the reverse section? That may be a timing issue with how fast the Frog Juicer racts vs how fast the EB1 reacts, and that may just be an incompatibility that can't be helped - though there is a setting on the Juicer for thoose situations when there are two Juicers back to back which might actually do something in this case as well.
I don't have access to AutoCAD at the moment, but I tried to make a sketch of your layout and taped it to the wall and took a photo. When all is said and done and the figure eight is unfolded and untwisted and the extraneous features are not shown, I think the layout from your first sketch looks like Figure 1. The layout shown on your latest sketch looks like Figure 2. I think. Your sketches still don't match, but neither indicates a reversing situation. No matter where you put the gap and no matter which side you attach the output from the auto-reverser, there will still be a mismatch of the polarities. I think.
It is entirely possible I still haven't got this right, so please forgive my intrusion. And if anyone can correct my sketches and/or logic, I'd gladly accept the correction.
Reading Randy's description of gapping, I believe the track drawn in green is the desired reversing section, although the section marked in red would be an isolated reversing section, just not as long as the section drawn in green would be.
I think your problem might be in the upper left corner of the overall picture on top, not the lower picture. It's a little confusing because the top of the picture is cut off but it looks like you flip flopped that track on one end. You might actually have another reverse loop hidden in there.
The one thing I thought was clear is that the EB1 shorts when he connects the second rail with the juicer. If it is properly gapped and no trains are running, and no garbage on the track, there shouldn't be any reversing going on nor should there be a timing mismatch between the juicer and the EB1
Randy mentioned there is a jumper on the juicer to make it a reverser instead of a juicer. I hope Gary took note of that comment.
There is a second reversing loop top left picture 1, but he says it isn't wired yet. That shouldn't be a factor for now.
If we call the top most mainline in pic 1 North and the bottom mainline South, the only crossovers between the two are the top left and the far right. I assume (should I assume) that all other tracks crossing over one another are bridges?
We get to Gary's pic #3 and the right reversing loop now looks like a siding instead. Robert I feel your pain. I'm stickin' to my jumper on the juicer theory though unless there is some other data need to know about.
Maybe it is the Frog Juicer that is confusing me. Why even bother with a Frog Juicer?
In any event, there are two reversing sections in Gary's first drawing. The double mainline is the figure 8. One reversing section is that connecting track on the upper left. That is gapped correctly. The other reversing section is the diagonal track in the center of the layout. It would be sufficient to gap the divergent end of each turnout that forms that reversing section.
Without the Frog Juicer, there should be no other gaps on the layout. I would restart from there. In my opinion, one of the feeders is crossed.
Rich
Edit Note: The only other gaps would be to isolate separate power districts from one another.
Alton Junction
BigDaddy I'm stickin' to my jumper on the juicer theory though unless there is some other data need to know about.
I'm stickin' to my jumper on the juicer theory though unless there is some other data need to know about.
Without the Frog Juicer, there only needs to be four pairs of gaps on the entire layout.
BigDaddy Robert I feel your pain.
Robert I feel your pain.
Hey Henry
Thanks. I'm not really in too much pain, but I still say there are no reversing loops in the first original sketch. Plenty of opportunities for shorts with all those track crossings, though. If someone can pick out a point, any point, on the main and show me the path a loco would take to return to the same point facing the opposite direction . . . then I 'd be in a little pain.
Instead of two yellow mains, paint one yellow and one orange. The result is two parallel mains with each forming a closed loop, one inside the other. Those blue lines are merely elongated crossovers that move traffic from the inner loop to the outer loop and vice versa from the outer to the inner. Neither blue line creates a reversing situation.
Then there's the issue of the red and black rail dots that appear to change aspect in the upper left corner of the sketch between Bus 1 and Bus 2 that Lone Wolf (I think) pointed out.
Whether the Frog Juicer acts as a juicer or a reverser, or whether the polarity is reversed in the various power districts just for the sake of reversing polarity, I don't think the layout of the tracks requires reversing wiring. Like I said, plenty of places for shorts to occur as it is.
I could be wrong . . .
Ok I understand that between the BOTH reversing loops I only need 4 gaps on on each end of the loop. I understand what Randy is saying about the location of gaps now on the loop in question.
I was under the impression that EACH Reverse Loop needs an AUTO-Reverser. The Dual Frog Juicer is also an Auto Reverser depending on the position of a jumper Which is set across the terminals as required. Don't I need an auto-reverser?
The Mainline Bus is connected to the "DCC IN" on the Juicer. Is that wrong?
If everything I say here is correct and I need an Auto-Reverser then no matter what I think there has to be wires crossed or something other than the wiring causing the short.
The short occurs about 2 seconds after power is turned on. I can hear some rapid clicking then it trips.
Thank you guys for taking time to help.
Can you make do without the Frog Juicer?
Robert, there are two reversing sections in that first drawing, the track on the upper left that connects with a mainline track and also thay diagonal track in the center of the layout.
gdelmoro I was under the impression that EACH Reverse Loop needs an AUTO-Reverser. The Dual Frog Juicer is also an Auto Reverser depending on the position of a jumper Which is set across the terminals as required. Don't I need an auto-reverser?
Depending upon the size of your layout and the number of trains running simultaneously, it would be best to use two auto-reversers, although some layouts can operate two reversing sections with one auto-reverser.
Rich you are correct. The Juicer is ONLY being used as an Auto-Reverser. I can put a different kind of auto reverser in if the Juicer could be causing the short.
I do have to have an auto-reverser, correct?
DCC Dual Frog Juicer and Auto-ReverserFor all DCC systems including NCE PowerCab. This board can be configured to use as an automatic polarity reverser for two frogs, a reversing loop, a turntable, a wye, or a crossing. It uses the same basic design as the hex frog juicer but has 33 Amp transistors so it can be used with multi-unit lashups and 10 Amp boosters. Setup is simple, connect the input to the DCC track bus, and connect the output wires either to two frogs or two rails. A jumper controls whether the two outputs act as a pair (i.e. an auto-reverser) or independently (i.e. a pair of frog juicers). Another pair of jumpers controls the current set point for switching, either 2 Amps or 4 Amps. When used for frogs or crossings generally 2 Amps work best and for an auto-reversing application, 4 Amps generally works best.
gdelmoro Rich you are correct. The Juicer is ONLY being used as an Auto-Reverser. I can put a different kind of auto reverser in if the Juicer could be causing the short. I do have to have an auto-reverser, correct?
So, the reversing section at the upper left is controlled by the MRC AD520 and that works OK?
But, the diagonal reversing section is controlled by the AR function of the Frog Juicer and that is shorting out?
I'm not suggesting that the Frog Juicer is faulty, but it may be wired wrong.
As far as gaps are concerned, it seems to me that the only gaps required on the diagonal reversing section would be on the ends of the divergent sides of the two turnouts that begin and end that reversing section.
One more thing, as I look at your second diagram, the AR should be wired on the input side from the main bus, and the feeders to the reversing section should be wired from the output side of the AR. Your diagram shows feeders to both the reversing section and the non-reversing section............or so it seems.
OK, I took a much closer look at that first diagram. It looks like you are creating a larger reversing section than just that the diagonal track. So, you want that reversing section to be not only the diagonal track but also that entire outer loop?
If that is the case, then you need to remove the gap on the divergent side of that lower turnout feeding into the diagonal section of track. That alone, however, may not eliminate the short but, hey, one step at a time.
Regardless of which way the reversing section ends up, I would temporarily connect the input wires coming into the AR directly to the reversing section, bypassing the AR. If there is no short the AR is suspect. If there is a short the track or wiring is suspect. Polarity won't matter as the section is isolated.
gdelmoro The short occurs about 2 seconds after power is turned on. I can hear some rapid clicking then it trips.
richhotrain gdelmoro Rich you are correct. The Juicer is ONLY being used as an Auto-Reverser. I can put a different kind of auto reverser in if the Juicer could be causing the short. I do have to have an auto-reverser, correct? ahh, OK, that helps clarify matters a bit. So, the reversing section at the upper left is controlled by the MRC AD520 and that works OK? But, the diagonal reversing section is controlled by the AR function of the Frog Juicer and that is shorting out? I'm not suggesting that the Frog Juicer is faulty, but it may be wired wrong. As far as gaps are concerned, it seems to me that the only gaps required on the diagonal reversing section would be on the ends of the divergent sides of the two turnouts that begin and end that reversing section. One more thing, as I look at your second diagram, the AR should be wired on the input side from the main bus, and the feeders to the reversing section should be wired from the output side of the AR. Your diagram shows feeders to both the reversing section and the non-reversing section............or so it seems. Rich
ahh, OK, that helps clarify matters a bit.
The upper left reversing section is not hooked up yet.
Yes Right side reversing loop is where the short is.
NOTE: I left the Juicer AR hooked to the Mainline bus and took a random piece of spare track and hooked it to that. NO short.
The original plan was to have that whole section from diverging from the main (Top Right) all the way to the intersect with the main again (Center Left)-the diagona so there were THREE feeders from the AR to make sure there was consistent power.
richhotrain OK, I took a much closer look at that first diagram. It looks like you are creating a larger reversing section than just that the diagonal track. So, you want that reversing section to be not only the diagonal track but also that entire outer loop? If that is the case, then you need to remove the gap on the divergent side of that lower turnout feeding into the diagonal section of track. That alone, however, may not eliminate the short but, hey, one step at a time. Rich
1st question = Yes. However I already closed the gaps and will add the gap on the turnout point to the Ferry Yard so that the reverse section will be from Top Right to the turnout point on bottom. The diagonal And the turnout will be part of the main line.
I'm going to cut a gap at the turnout point next.
Connecting the AR to a small piece of track may indicate the AR is fine. Bypass the AR and see if there is a short in the reversing section. You could also temporarily hook up the other reversing section using the AR and see if that shorts. If no short then the track and wiring in the problem section is suspect, if it shorts the AR or the wiring leading to the AR is suspect. Moving the location of the gaps shouldn't affect the shorting problem unless in doing so the problem section of track,( if there is a problem section of track) is removed from the reversing section. The cause can only be AR, wiring, track, or a combination of some of the first three. Proving the AR reliable, or not, is in my view the first step.