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Atlas Mark IV turnout frogs in DCC

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  • Member since
    August 2003
  • From: Collinwood, Ohio, USA
  • 16,367 posts
Posted by gmpullman on Thursday, August 16, 2018 10:02 PM

Mark R.
I don't know what you track layout is like beyond both ends of the two switches, but you say you get a short when you connect the two switches together

Or do the turnouts complete a reverse loop? Such as a crossover in the middle of a dog-bone?

Can you give us a sketch of the track plan and show where these turnouts are in relation to that?

I waited over a minute for the Photobucket photo to load then gave up. Reaffirms why I left Photobucket.

Good Luck, Ed

  • Member since
    April 2004
  • From: Ontario Canada
  • 3,574 posts
Posted by Mark R. on Thursday, August 16, 2018 9:16 PM

I really hope those blue and yellow feeder wires aren't permanent !

I don't know what you track layout is like beyond both ends of the two switches, but you say you get a short when you connect the two switches together .... sure you don't have a pair of feeders reversed on one side and when you insert the two switches it causes a short ?

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

  • Member since
    February 2008
  • 2,360 posts
Posted by kasskaboose on Thursday, August 16, 2018 9:12 PM

Makes sense.  Regardless of where the probes function, the train won't move through two turnouts connected together.  How to have power carried through the turnouts connected together so a train can go from one turnout to the other in DCC?

As I wrote, the Atlas rep's suggestion--using a snap relay switch--didn't make sense for DC.

Thanks!

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, August 16, 2018 8:29 PM

 What makes you think there is a short at that location? The first two photos showing a 0 volt reading? You have both probes touching pieces of the frog that are all one chunk of metal, so there will always be 0 volts there. If you switch to Ohms/Continuity, it should beep with the probes there. The real test would be to touch the frog with one probe, and one of the other rails with the other probe - there should be no continuity and no voltage even with the power turned on.

                                         --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    February 2008
  • 2,360 posts
Posted by kasskaboose on Thursday, August 16, 2018 8:20 PM

This might help everyone! Photobucket is being a royally annoying, so it took forever to get the photos I sent to Atlas.  Here they are:

http://s44.photobucket.com/user/leekass/library/?sort=3&page=1

Iwould apprecite some seasoned thoughts on the short.  The red thumb tac are the locations of the short on the turnout.  It might be easier to look at the pictures in a larger size by clicking them.

Thanks

  • Member since
    December 2015
  • From: Shenandoah Valley
  • 9,094 posts
Posted by BigDaddy on Thursday, August 16, 2018 5:39 PM

I just checked my new, uninstalled code 83 Atlas IV Customline turnout.  The frog rails and not in continuity with each other or the frog.

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    December 2015
  • From: Shenandoah Valley
  • 9,094 posts
Posted by BigDaddy on Thursday, August 16, 2018 5:29 PM

I thought we solved this on one of your last threads. 

The frog rails, the 2 rails on the normal and diverging route that are next to the frog (red and blue), but separated by a tiny piece of plastic from the frog, should never be the same polarity as each other, out of the box. Nor should there be any continuity with the frog.

 I can't say for certain that there never would be a manufacturing defect that would create continuity, but I think it's a highly unlikely failure mode.  But what you are saying is you have this: ignore that the frog is hot.

For purposes of this discussion, you can ignore all the jumpers and "options"

I never used snap switches, so someone will come forward and tell me if I'm wrong, but they are just DPDT switches, meaning they can change the frog from red to blue and back again.  Unless they are linked to some lights on a control panel, you are going to have to remember (every time) to throw them before the loco hits the frog or you will have a short.

It might be time for us to have a look at your track plan where this problem occurs.

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Thursday, August 16, 2018 5:02 PM

 Unless they vastly changed something, there is no need to use plastic joiners with an Atlas Cutsom Line turnout. The rails pass straight through and are unconnected. Like I said - lay 2 pieces of straight track on top of one another, one at an angle to the other, this is an Atlas turnout, the right side rail is the right side rail on all 3 legs, the left side rail is the left side rail on all 3 legs, and never do they touch. The frog is completely isoolated from any rails.

 You do not NEED to power them, but as the frog gets longer, the dead zone gets longer and it i more likely that locos will stall when the wheels are on the frog area and it is not powered.

 If you get shorts without plastic joiners - you probably have a reverse loop.

                                    --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    February 2008
  • 2,360 posts
Atlas Mark IV turnout frogs in DCC
Posted by kasskaboose on Thursday, August 16, 2018 4:28 PM

Atlas was kind to help me with the electrical short I'm encountering when connecting two Atlas Mark IV #8 turnouts together.  They gave me detailed instructions about using a snap relay.  Is that necessary for DCC?  The Mark IV have non-powered frogs (it says that on the back of their package).  How to wire the frogs so they get power?  I found that to avoid a short, these turnouts need to get connected together with plastic joiners (yes, I checked with a multi-meter).  The issue is there is then no power running through.

All the other layouts are fine since they connect to sidings. 

Thanks,

Lee

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