Ok I just the first wye turnout I ever used today. It’s a atlas code 100, And when I connect it the DCC system (MRC Prodigy Express) starts blinking, saying that there is a short somewhere. This only happened when the turnout it connected to the track. I’m not sure why It is doing this, I neve had any problems before with any atlas code 100 switch track and my dcc system. If someone can help it would be apreciated.
The Atlas turnouts are ‘DCC Friendly’ - Are you sure you did not connect it in a Wye or Reverse Loop configuration? You still need insulated gaps no matter what turnout you are using in that case.
If there is no Reverse Loop or Wye, then remove the turnout and test it with a meter to see if it has a short.
Jim
Oh I was not aware of the reverse loop problem that can occur, what parts would I insulate? or how would I go about setting this up. So it would work.
The turnout probably feeds power down the lined route, so you may get a short if the route it wants to feed is also fed from a turnout on the other end of that segment that is trying to feed power of the opposite polarity. I have the Shinohara #6 and fed it from the single end. I learned quickly to gap it at the ends of all three routes. Even then, when the first set of power-transferring axles on any item crosses the gap, it will stop and short if the route is not lined already on the wye for the oncoming train to pass through the wye.
I still have the odd goof, but I have mostly remembered to line the entire route first. The problem, BTW, could be either of the two throwbars. You may think it is one, but the short stays until you throw the other, too. At least, that is what I run into the very odd time. Usually I can pick up the miscue quickly with a cursory glance.
SO I should Insulate the track completely and also ensure at all times that the switch tracks near the wye are lined up correctly? Is this correct?
I would back up and make sure you understand what you’ve got, and what the problem is before you start doing things that may or may not be helpful.
First, do you have a reverse loop situation? From reading you initial post it almost sounds like just adding the turnout cuases a short. Are you using the wye turnout in a wye (as is turning trains around) configuration? I think it makes a lot moer sense to understand what’s up first.
Here’s a rough diagram of what I got.
A wye, not caused by the turnout by the track configuration, will inherently cause a short, like a reverse loop or turntable. To see what is going on, color code each rail as a polarity and follow the rails. You’ll see where one polarity suddenly runs into the other, causing a short. To prevent this, you need to isolate the wye configuration and set up the electricals to be able to reverse the polarity to this section, or try one of the DCC automatic polarity converters on the market.
Are there any topics or turtorials on this topic floating around the forums?
This is very helpful. You do now have a reversing section. To see this put your finger on one rail at the ‘input’ to the wye. Move throught he wye and onto one of the legs. Then back up onto the other leg. Then move back through the wye turnout. Your finger has changed rails, or your train has changed direction. As has been said it is the track configuration, and not the turnout itself that does this. It is a somewhat unfortunate circumstance that the configuration and the turnout have the same name, since they don’t have to both exist together, thought hey often do.
So yes, something needs to be isolated.
About 2/3rds the way down this page:
http://www.wiringfordcc.com/track_2.htm
are some methods. Since it appears that the wye is stub ended I think I would gap (both rails) at the frog ends of the two diverging routes at the bottom, and then either manually or automatically make the entire wye the reversing section.
Here is a diagram for proper reverse loop wiring. I drew it with XtrkCAD & paint. Basically what you need to do is buy a reverse loop module (technically you could use a booster, but I don’t feel like drawing one for that and it is WAY more expensive.) like a Lenz LK100 which can handle up to 5 amps of current or a Digitrax AR1 which can handle up to 8 (!) amps of current. You isolate one leg at the turnouts (this is so an engine like a big boy wont bridge the gap & defeat the purpose of the isolation) connect two wires for each rail on the leg to the auto reverse unit per instructions. You then connect your AR unit to you power bus (if you do not have one, then you must connect them to the rails.) per instructions.
I like that better.
A Wye is electrically the same as a reverse loop. Whether you are using ‘old’ DC or DCC control, you must wire the Wye up as a reverse loop. Suggest you obtain reverse loop module for your DCC system and fit it according to the instructions with the product. Have fun - Baznavman - Scotland.
Or the cheaper solution is to use a DPDT switch to throw the wye turnout Wire it so that when the turnout is thrown to the left leg of the wye the polarity matches the left leg of the wye and when the turnout is thrown to the right, the polarity matches the right right leg of the wye. A DPDT switch is less than $5, a reverser module is $30-50.
Dave H.
On a two rail system, any track arrangment where a train can move through a section of track that reverses its direction back on the piece of track where it started will have the “reversing loop” problem. This includes reversing loops proper, Wyes, turntables, crossovers on a dog-bone, diagonal cut offs through a loop, etc.