Hey All;
My double main line is laid and ready to go, and I,m running DCC, so here,s the question, since I,m planning to install a crossover will I have to gap (or) insulate the actual turnouts where they meet to avoid a short??? JUst wonderin" thanks.
TrainsRMe1
Modeling a what if modern era Union Pacific subdivision from Eugene Oregon to Coquille Oregon
Trainsrme1,
Your question,would be easier to answer,if you would include,what turnouts you are using,or what kind you plan on using,that will make a difference,on how to wire it and if you need insulated joiners..
Cheers,
Frank
As Frank says, it all depends upon the turnouts you are using and the track plan that you are using.
Typically, a crossover on a double main line needs no special wiring since the wiring is in phase. In other words, the left rail on both mainlines has feeders from the same bus wire and the right rail on both mainlines has feeders from the other bus wire. Complications arise if the two mainlines are wired opposite each other. Another wiring problem can occur if the crossover is part of a reversing section. So the actual track plan is critical to the right answer to your question.
The other issue is the type of turnout. Is the frog live or is it not? Atlas turnouts, for example, present no special wiring problems. Same for Walthers and Walthers Shinohara. Same for Peco Insulfrogs, but Peco Electrofrogs raise special wiring issues.
Tell us more.
Rich
Alton Junction
Hi Rich,
My turnouts are Atlas and the track plan is a dogbone.
Well, Atlas turnouts need no special wiring, so the only question relates to the dogbone.
Can you post a track diagram or describe it?
If it's a dogbone, two loops with a narrow neck, and you put a crossover between the parallel tracks of the neck, that's a reverse loop and you will need to wire accordingly.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Hey Rich,
Yes I can describe the plan, it's a around the room plan with the mainline going through three towns, each town has a classfcation yard, at each end of the plan is a reversal loop, I'm using two Digitrax AR1 decoders to operate each loop, My track plan is like the Santa Fe RR, Southern Dist ,track plan, found in the October 2009 Modelrailroader
So:
1. You have taken that plan and put a loop at each end instead of bridging the door.
2. You have made it a double track main line, such that the loops aren't really reversing loops but the ends of a dog bone.
Right?
Your question really depends on how you are going wire it.
If it is wired as a true dog-bone there should be no need for reversing units in the loops, instead as this thread implies in the crossover.
On the other hand if you have wired it as a double track first, with the loops thrown on the end. Then there is no need for concern with the crossover(s), but the reversing loops need treatment.
Maybe TZ understands it without a track plan to visualize it, but I don't.
The Santa Fe RR, Southern District track plan in the October 2009 issue of MR is not a dogbone.
Where are the reversing sections and where are the crossover(s)?
You gotta tell us more or show us your track plan.
I wish I could show you my track plan, but I have problems in downloading pic's from Photobucket and webshots!!! Sorry about the confusion, I will say that the plan is a around the room plan with reversal loops at each end, NOT A DOGBONE I have the double main line ONLY in my towns, with the crossover in one of my towns, I hope this helps, Thanks
TrainsRMe1,
Can you email a copy of the track plan, so we can post it?
Once we see the plan, we can all jump in and give you some help.
Without a plan, we are only guessing, and that is not going to help you at all.
Trainsrme,
If I understand you correctly from your description,,you do not have a double track main line at all..You have one track going,(as a example) going North,goes around the loop,comes back going South,on a track that is parallel, to the one going North..Is that correct?
Here are two examples of a crossover. I have colored one rail blue and one rail red to help you visualize the wiring.
To best understand the examples, trace the crossover from the upper left to the lower right.
In the first example, the rails match up so there is no reverse polarity occurring at the connection on the lower right, as seen in the circled area. No special wiring or gapping required.
In the second example, the rails do not match up so there is a reverse polarity occurring at the connection on the lower right, as seen in the circled area. This will require some special wiring and gapping to prevent a short.
It is always helpful to color the rails in this way to more easily visualize reverse polarity problems. Often, it depends upon how you are wiring the rails. Sometimes, reverse polarity situations can be avoided by careful wiring. Other times, reverse polarity situations cannot be avoided and special wiring is required.
Thanks I will give that a go, Breaking News:: I went out this morning and installed my crossover and all went well!!!! now on to the ground throws!!! Thanks Rich for your example above, I will also TACKE and win the battle with uploading my photos!!!! Take care MRRDER's have a great weekend!
Trainsrme1
So, no reverse polarity issues?
No need to gap rails?
Congrats.
Smooth sailing, I posted a pic of the crossover, in a new post, check it out, I'm still learning how to upload pic's with the help of my daughter!!