# DCC, Rail Joints and Turnouts



## DavefromMD (Jul 25, 2013)

I use sectional track. It is what I have and with my 4 x 8 is best for me seeing as I change the layout around about once a year. I use Atlas code 100 nickel silver and snap switches.
I currently run DC.

I've been doing more reading on DCC and I see a lot about having good connections thoughout the track. A key concern in what I read talks about there needs to be enough current flow to trip the circut breaker if a short occurs. If there's not enough current to trip the breaker, bad things can happen to locomotives, track, wheels, and power supply. Much of what I read seems to be geared toward larger permanent type layouts. Obviously I don't want to solder rail joints. I have 2 ovals with a few sidings. Outer oval is about 20 running feet of track, inner a bit less. I currently have 2 power drops per oval. Would that be sufficient for DCC or would I have to increase that to maybe 4 drops per oval?

I also have a concern about the turnouts. Occasionally with metal wheels on rolling stock, a spark will arc across to the power connection to my turnouts. Not a problem with DC, but with the increased amperage of DCC would this potentially cause the same type of damage as a short - or at the least damage the track, wheels, or turnout motor?

I also read where it talked about possible shorts caused when trains cross the frogs on turnouts.

Maybe I'm doing too much research. Just as I get myself convinced to go to DCC I read something that makes me think maybe sectional track and DCC don't go together too well.

Any insight will be appreciated.


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## kix662003 (Mar 8, 2013)

I use Atlas Code 100 N/S Snap track and haven't had problems with DCC shorts on Atlas turnouts. The newer ones are approved for DCC. I have bus feeds every 5-feet where insulating rail joiners (on both rails) are used to isolate possible shorts. I thought about using circuit breakers or the 1156 auto light bulbs in case of a short, but never did. The internal protection in my power supply shut the power off when liquid shorted the rails once, and there was no damage to the BLI locomotive. No incidents since. I use Bachmann's EZ Command to run 2 DCC trains at one time. It's just enough for my two sound equipped BLI engines, and plenty for the Bachmanns. I have the BLI DC Master hooked up to my MRC Dual 280 Tech 4 to check or change CVs, and control sound when run BLI engines on analog tracks. I don't know about DCC on turntables. My turntable is in the DC powered section of the yard layout, still using all Code 100 Snap track. I'm attached to my analog engines and plan to keep them as manufactured (with the exception of LED lights and Kadee couplers). The main line and the main line siding on this layout does not touch or connect to the DC branch line or service yard off the turntable. Isolated turnouts between AC and DC tracks wouldn't be enjoyable for me, and I have grandchildren that like to run Grandpa's trains.


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## DonR (Oct 18, 2012)

The major drawback to using sectional track is that the number
of joiners is increased dramatically. Each one has the potential
to develop high resistance and drop the voltage to the track.

If your layout is in a climate controlled area this would be less
of a problem.

For DCC (or DC for that matter)
I would use 4 track drops on your 4 X 8 layout for each
oval. You should not need any drops for spur tracks.

You should actually expect little problem with DCC on the layout that
you describe.

Some turnout frogs have only a tiny sliver of insulation between
the diverging rails. Sometimes wide metal wheels will span these 
insulators and cause a spark or if going slow enough trip the
short detector. This can easily be resolved. One way is to
use an insulated joiner between the diverging rails and the
connecting rail. I go even easier. I Just put a tiny dab of
clear nail polish where the insulator is or where you see
a spark when the train runs thru. That prevents the
metal wheels from shorting. Obviously, let it dry for a few
minutes before running locos over it.

The 'serious damage' to locos and wheels in the event of a short
that you have read about applies to large layouts with
high amperage boosters. You would not require any such for
your layout. The power source for a DCC controller that would
be suitable for you would simply trip it's 'breaker' in the
event of a short. Most of these occur when a turnout has
been set against a loco and it's metal wheels short the
point rail when they hit it. Cars with metal trucks are
more likely to do the same when derailed. But that's
what short detectors are for. Not to worry. No damage
occurs.

So, just relax and enjoy the many features that are
yours with DCC powering your layout.

Don


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## RT_Coker (Dec 6, 2012)

Dave,
I have a DCC layout that uses code 100 nickel silver sectional track with roadbed (not Atlas). I cover the track when doing scenery and haven’t added anything to the track. It is 78” x 160” with two loops and a large yard. It has one centrally located power connection (excluding the programming track section). It is two years old in a dehumidified basement. So far I have had just one rail-joiner problem a loosely connect rail-joiner (most likely because the track was bought used). 
I am not recommending this approach, just trying to give you some of the different ways of making and using a layout that can factor into your decisions.
Bob


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## DavefromMD (Jul 25, 2013)

Thanks guys for you input. All very valuable and certainly eases my mind over what I have read (mostly on the internet other than here). My mind mind was starting to reel over what I read and you guys gave me the simple answers.


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