#5 Atlas Switch Shorts With Lighted Passenger Cars

I don't know about this but I wonder if there's a micro switch throwing power to that silver rail ( or center rail?) when the points are thrown? Otherwise, I could see why this is happening. There must be something that is now stuck?

Just run really fast!

I'm off to see the Atlas site for details about their switches.

somehow the wie connecting the rollers is shorting out the the hot and middle and outer rail when the lighted  car crosses. 2 diodes from the rollers in opposing direction9(polarity) would prevent this since current will not conduct through opposing diodes the resulting voltage to the leds would be half wave with a capacitor this should work fine.for easy mounting 2 leads of a bridge rectifier can be used

.Dale H

There are no micro switches for power routing in Atlas switches.  I've tested an O72 and an O72/54 switch, and the silver rails like the one circled above are not continuous with the points or outside rails no matter how the switch is thrown.  So something happened on this #5 switch to make it continuous with the point.

Dale, I'm sure that would work, but I don't feel like doing it to all my passenger cars, cabooses, locomotives, and sound freight cars.  I'll probably have to pull the Dremel out and shave off the rail so it is no longer making contact with the point.

before going through the trouble of shaving the rail or such, try painting it with nail polish in the areas that are trouble, and see in the small sections that are covered will be a problem for any of your engines.   If everything runs fine with a couple painted over spots you can modify the track if you want, but may just be easier to leave them painted over and touch-up as needed.  

JGL

This coming from a two rail DCC mindset, Check for wheel gauge?? 

Is there contact between the open point and the diverging rail section?  Press the offending car's flanges against the tangent stock rail to avoid the back of the wheel touching the open point.  Somehow it seems like the diverging rail is being energized.

you could install poly fuses into the passenger cars between the rollers.

I just find it odd that something has changed. I am a 2 rail guy. Not much experience with 3 rails.

When I saw where it was sparking, I thought of wheel gauge as well, but why would they all of a sudden change, and all 8 cars at once?

That point does look somewhat close to the stock rail, is that the same size gap on all points? 

Just for testing, run some electrical tape along the back edge of that point and see if the short still occurs.

Maybe run the problem cars through that area at night with the lights turned off to absolutely isolate the spark source.

What happens if you run that same car through the diverged side of the switch?

Im pretty sure that that small section of rail (the silver rail) should be electrically isolated. If it is an issue that has just started happening after previously working properly, I'm betting there is something electrically connecting that section to something. Could be something simple like some conductive debris. Some things to try would be visually inspecting, vacuuming with a shop vac, or blow some canned air in that area. 

If you are still having an issue with that switch give me a call at Atlas 908-687-0880 X- 7142. I would be happy to help.

Steve H

Check for electrical continiuity between the frog and the converging rails (between the frog and the points). There should not be any continuity. If there is you need to open the gap between the frog and any offending converging rail.  

Steve Horvath posted:

If you are still having an issue with that switch give me a call at Atlas 908-687-0880 X- 7142. I would be happy to help.

Steve H

What hours are you there?

ctr posted:

Check for electrical continiuity between the frog and the converging rails (between the frog and the points). There should not be any continuity. If there is you need to open the gap between the frog and any offending converging rail.  

I have continuity between the converging rails and the points, as I stated above, and this is why it is shorting.  Why it started happening when it didn't before IDK.

sinclair posted:

I have a #5 Atlas switch on my loop that just started giving me issues.  I've had it for a while, and run these very same passenger cars on it and not had any issues until this week.  When passing over it my 180W brick tripped.  At the time I didn't know why.  I reset and started up and all was good until I noticed sparks on the switch as my cars went over it and then the brick tripped again.  I investigated with my lighted passenger cars, the VL sound reefers, and the new sound PS-1 box cars.

When any of the cars with two rollers goes over the switch, it shorts the track when the rollers fall on the locations of the two circles.  It looks like as the train wheels pass the points, it arches from the outside rail to the point, which is connected to the rail for the turnout.  I have been running just fine over the switch for a few months.  Any idea on why it started doing this, and how I can fix it?

The circled sliver rail is not electrically connected to the frog, only to the point.  Should it be floating from the point too?

None of these cars are new? Same old rolling stock? Have a friend with Atlas track, IIRC the gold rail you have circled is normally not connected to either "+" or "-" so there is no potential. If the flanges are too wide or there is not enough clearance for them and the pick up roller is energizing the gold rails you may get a short. In reading your posts there is no continuity between any of these rails and it does not occur when using the diverging route I'd look to see if the roller isn't passing current to the moveable rail at your arrow with the flange making a short. As mentioned covering that curved rail with tape and if the problem stops would help you trouble shoot it.

My normal hours are 7:00 AM - 9:30 AM Mountain T Z. I return calls ASAP if I happen to be out after that. Leave a message and a good time to reach you and I will get back to you.

Steve H

@Steve H.  Thanks for the reply, I may call you if we can't figure it out here (I hate making people work extra hours, and from 6:30AM to 4:30PM MTZ I am no where near my layout.).

Okay, let me lay the facts all out in one place.  Below is the switch in question, each rail of interest is color coded.

-Travel through the switch is how it is shown.

-When pickup rollers of the same car touch the orange and red rails, it shorts the transformer.

-When this happens I can see sparks from the yellow and pink rails at the location of the pink dot (Lights do not need to be off to see it!).  There is also evidence of it at this location.

-These same cars have been running over this switch for at least 2 months without an issue (Once or twice a week for 10-20min each run.).

-The train has 6 lit passenger cars and all 6 do it, as well as 3 VL sound reefers and a new sound boxcar.

-It is a newer Atlas switch, but not the latest batch.

-The orange and yellow rails are electrically continuous no matter how the switch is thrown.

-The orange and purple rails are not electrically continuous.

-The green rail is not electrically continuous with either the purple or blue rails.

My thought is I need to find how to electrically isolate the yellow and orange somehow.  Any ideas how I can do this, what caused it, and how can I keep it from happening to my other Atlas switches?

Looks like the wheel is touching the yellow rail and thus connecting it to the outside rail, that results in a short when a roller hits that rail.

Put some tape on the outside of the yellow rail as a test and see if that resolves the issue.

You may have to pull the switch up and flip it over. I would check the jump wires on the B side and see if one has come loose and it making contact with the diverging rail. Some how this rail is getting grounded.

By the sounds of your post, the orange and yellow should then not be continuous?

I'm only guessing because you said "The green rail is not electrically continuous with either the purple or blue rails."

I don't have any Atlas 3 rail switches to check. Compare with your others.