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A few more "basic" DCC questions for you............

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A few more "basic" DCC questions for you............
Posted by mobilman44 on Wednesday, November 19, 2008 12:50 PM

Hi!

As a longggg time DC model railroader, I have decided to jump into DCC in my upcoming HO layout rebuild (after the Holidays).  I've asked you for advice and answers in previous postings, and you all came through with flying colors.  Of course I have some more basic (?) questions, and here are a few more I hope you can enlighten me about.

-  Assuming the use of code 100 NS flex track, with all joints soldered, and 14 gauge power bus lines (less than 25 ft runs) with 20 gauge feeders (less than 2 ft runs), what kind of spacing between feeders will suffice to keep a strong signal (on clean track of course)?  Note the layout will be run off of two 5 amp or two 8 amp boosters and divided into 4 or 6 blocks.

-  I've asked this before, but have to ask again to assure the I didn't misunderstand the answer.  Will Atlas code 100 turnouts (customline) cause the wheel shorts that I read so much about?  I ASSUME a dead frog would prevent this - or is it the other way around?

- When you have a number of locos stopped on the layout (ie. in an engine terminal), can you turn them off with the DCC controller so as to reduce the layouts power consumption, or do you have to switch off the power to the tracks the locos are on?

Thanks!!!!

Mobilman44 

 

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by MRCProdigyrailroader on Wednesday, November 19, 2008 1:20 PM

mobilman44

Hi!

As a longggg time DC model railroader, I have decided to jump into DCC in my upcoming HO layout rebuild (after the Holidays).  I've asked you for advice and answers in previous postings, and you all came through with flying colors.  Of course I have some more basic (?) questions, and here are a few more I hope you can enlighten me about.

-  Assuming the use of code 100 NS flex track, with all joints soldered, and 14 gauge power bus lines (less than 25 ft runs) with 20 gauge feeders (less than 2 ft runs), what kind of spacing between feeders will suffice to keep a strong signal (on clean track of course)?  Note the layout will be run off of two 5 amp or two 8 amp boosters and divided into 4 or 6 blocks.

-  I've asked this before, but have to ask again to assure the I didn't misunderstand the answer.  Will Atlas code 100 turnouts (customline) cause the wheel shorts that I read so much about?  I ASSUME a dead frog would prevent this - or is it the other way around?

- When you have a number of locos stopped on the layout (ie. in an engine terminal), can you turn them off with the DCC controller so as to reduce the layouts power consumption, or do you have to switch off the power to the tracks the locos are on?

Thanks!!!!

Mobilman44 

 

1. With your bus lines at that length, it doesn't really matter.

2. No. I use them on my layout almost exclusively. It might happen with a Bachmann Shay, but other than that, they work great.

3. You will have to switch the track off, but when at idle, locomotives don't use much power at all unless sound is on. I actualy leave my DCC system on overnight to charge my wireless controler.

The Master Hand!!! Modeling the modern BNSF and Norfolk Southern... On the same layout!!!
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Posted by MisterBeasley on Wednesday, November 19, 2008 1:27 PM

I would still go by the feeder spacing of every 3-6 feet for rock-solid reliability.  It's really more for redundancy than for signal strength.  Since you plan to solder your joints, the longer end of that range should still give you very reliable performance.  I think it's more important to make sure you feed both sides of every turnout.

I don't think Atlas turnouts have wheel short issues.  Peco turnouts certainly do, but that's because their Insulfrog design has a very small spacing between two oppositely polarized rails coming into the frog.  That small gap can be bridged by metal wheels, causing a short.  The standard solution is to paint the gap with an insulator, typically clear nail polish.  My Atlas turnouts have more of a "dead zone" problem, because the plastic frogs are so long, and the points themselves don't have a robust electrical connection to the stock rails.

An idling, non-sound DCC engine with the lights off consumes almost no power.  A sound engine will use some power to produce the idling sound.  Most, if not all, decoders allow you to "mute" the sound, but I'm not sure if that just shuts down the output, or if it shuts off all the processing and thus saves all the power.  Some decoders have a "shutdown" sequence, which will put the engines into a "sleeping" state.  I suspect that the engines use very little power in that case.

Still, I have shutoff toggles in my roundhouse.  With my Lenz DCC system, the "mute" command does not carry over after you shut the system down and power it back up again, so if I've put engines away in the roundhouse, they will all be squawking again the next day.  (My guess is, this feature is in the decoder, not the DCC system, because the indicator for the function comes back with the power.)

If you have illuminated passenger cars or perhaps cabeese that draw track power, you might want to provide a siding with a shutoff switch to store them, so you don't need manual shutoffs for each car.

It takes an iron man to play with a toy iron horse. 

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Posted by Stevert on Wednesday, November 19, 2008 1:31 PM

mobilman44

Hi!

As a longggg time DC model railroader, I have decided to jump into DCC in my upcoming HO layout rebuild (after the Holidays).  I've asked you for advice and answers in previous postings, and you all came through with flying colors.  Of course I have some more basic (?) questions, and here are a few more I hope you can enlighten me about.

-  Assuming the use of code 100 NS flex track, with all joints soldered, and 14 gauge power bus lines (less than 25 ft runs) with 20 gauge feeders (less than 2 ft runs), what kind of spacing between feeders will suffice to keep a strong signal (on clean track of course)?  Note the layout will be run off of two 5 amp or two 8 amp boosters and divided into 4 or 6 blocks.

You should drop feeders from every piece of flex track, although with soldered joints you could probably get away with feeding every other piece.  I'd also shorten those 20 gauge feeders to no more than 12 inches.

mobilman44

-  I've asked this before, but have to ask again to assure the I didn't misunderstand the answer.  Will Atlas code 100 turnouts (customline) cause the wheel shorts that I read so much about?  I ASSUME a dead frog would prevent this - or is it the other way around?

  There are a lot of different opinions on this.  But for what it's worth, I use those exact same turnouts, with the frogs powered, on my DCC layout and I haven't run into any wheel short problems whatsoever.  

mobilman44

 

- When you have a number of locos stopped on the layout (ie. in an engine terminal), can you turn them off with the DCC controller so as to reduce the layouts power consumption, or do you have to switch off the power to the tracks the locos are on?

You should set the speed to zero (and be sure it's really at zero) and turn off the lights/sound (and if you use Digitrax, you should dispatch the loco).  In that state, the decoder will be able to immediately respond if called up by a throttle.  It will draw a tiny amount of current in that state, but unless you have dozens of locos on your layout in that condition it won't be drawing enough to make a difference (unless, of course,your layout is under-powered to begin with).   

mobilman44

 

Thanks!!!!

Mobilman44 

 

 
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Posted by jrbernier on Wednesday, November 19, 2008 1:42 PM
  1. 3-6 feet between feeders.  Do not rely on rail joiners(even soldered ones).  The solder bond can break.  I know it is a pain to make all of those connections, but it pay dividends in the future.
  2. Atlas Custom-Line turnouts are 'DCC Friendly' - The insulated(dead) frog can be powered if needed.
  3. When a DCC/Sound engine is parked and 'Dispatched'(not using a system 'slot' and not tied to a throttle), it still draws some power.  If a short occurs and the booster shuts down/resets, a sound engine usually draws a lot of power to charge the capacitor in it.  It is the 'restart' that draws a lot of power.  If you have a lot of 'parked' engines, you can still use panel toggle switches to electrically 'kill' them so they do not draw power.

Jim Bernier

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by mobilman44 on Wednesday, November 19, 2008 5:16 PM

Thank you all!

  It is satisfying to know that you all had pretty much the same answers to my questions, which means I can take them to the "bank".  What's almost scary is I am starting to understand this DCC stuff.  Of course I haven't given much thought about decoders or operations yet - other than thinning out a number of my "not so DCC friendly" locos. 

Thanks again,

Mobilman44

 

 

ENJOY  !

 

Mobilman44

 

Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central 

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Posted by cacole on Wednesday, November 19, 2008 5:44 PM

I really don't know why so many people claim that Peco turnouts cause shorting problems.  We have close to 50 Peco code 100 Insulfrog turnouts on our HO scale club layout and I used Peco code 83 Insulfrogs exclusively on my home HO scale layout, and we have never had a single short circuit problem with any turnout.  At the club we run both DC and DCC, and my home layout is DCC only.

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Posted by rrinker on Wednesday, November 19, 2008 7:12 PM

cacole

I really don't know why so many people claim that Peco turnouts cause shorting problems.  We have close to 50 Peco code 100 Insulfrog turnouts on our HO scale club layout and I used Peco code 83 Insulfrogs exclusively on my home HO scale layout, and we have never had a single short circuit problem with any turnout.  At the club we run both DC and DCC, and my home layout is DCC only.

 

Probably from this diagram from Wiring for DCC by Allan Gartner:

 

                                --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

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Posted by jrbernier on Wednesday, November 19, 2008 8:31 PM

  Trust me on this.  A Peco 'Insulfrog' can/will short out at the 'point of the frog' if the tires are a little wide on an engine.  This can be 'fixed' with a little 'nail polish' painted on the tip.  Sometimes you need to do this more often on a club layout.  Also check to see if gauge of the drivers is good.

  This was not a big issue on older DC layouts as the voltage was lower and you had only 1-2 amps maximum out of most power packs.  Also the power packs usually do not have fast acting electronic breakers like most DCC boosters.  With DC, an engine would barely short as it passed over the frog.  The power pack would usually not shut down, and if it did - only the train on that power pack was affected.

  Now, fast forward to DCC.  A full 14-15 volts is on the rails all the time, and usually has at last 5+ amps of power it can deliver.  Your DCC engine shorts across that frog, and the booster goes into shutdown - Everything in that booster/power distrct is affected.  Older engines that performed 'flawless' on DC now short on DCC - wider tires are shorting across the tip of the frog.

Jim

 

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by selector on Wednesday, November 19, 2008 9:07 PM

As a user of Peco Streamline Code 83 #6 Insulfrog turnouts, I can tell you without hesitation that they do, indeed, have shorts issues, and for the reason stated and shown above.  It would get worse as the frog # goes up because the frog rails are in proximity to each other for that much longer due to the reduced angle of diversion between them.  If you are using Proto 87 wheelsets, I would guess that you are home free.  I don't, and neither do something in the order of 19/20 HO modellers.  With our somewhat wider tire surfaces, and always metal on driven items, you can count on shorts at least part of the time unless you paint both rails with a non-conductive coating for a safe distance into their diversion.  Usually 1/2" is lots, perhaps longer with a longer turnout if Peco can supply it.

I do disagree, at this point in my modelling experience, about the need to feed every single piece of contiguous rail.  I don't disagree that it should be the best way to prevent drop-out along a rail section...clearly it would be the best way, but it is not necessary in my view.  If you can solder a joiner between two pieces of contiguous rail, no matter the code or who makes it, you can include a usable feeder in that soldering action and get power very nicely, and reliably, to the entire length.

For what it is worth, I currently have an ad-hoc "staging shelf" yard about 5' off my layout with a hand-made lumber "bridge" that allows access to it from a point at the corner of my layout.  This staging is on a 14"X100" white do-it-yourself shelving section, the laminated kind you pick up at Wal Mart, say.  All that powers the the four classification tracks, a hodge-podge of flex and leftover EZ-Track (I'm serious), and the butt-end track to the corner of the layout that leads to this temporary lumber bridge, are two sets of metal joiners.  Nothing is soldered.  Yet, back about 3' from this corner butt-end track is the only set of feeders, 20 gauge, that feeds the entire system, bridge and yard, through these metal joiners.  I have removed and replaced this bridge a number of times, so the joiners are no longer pristine.

I can give you every assurance that I can go over to my power bar right now, power up my DB 150, and any loco on that distant yard, fed by the thin pair of distant feeders, will come alive, make sounds, and respond to my throttle commands some 18 feet way.  For nearly two years now, they have done so...every single time.  I am talking about a total of 30' of track powered reliably, so far, from one end by one thin pair of feeders...including the metal joiners between about four turnouts.

Why is that?  It is because the engineering principles are sound to begin with.  What confounds the construction is improper use of the materials.  My placement of all these interrelated items is stable, solid, careful, and purposeful.  I thought about it, and executed it well.  I continue to be rewarded by my process, both in reliablity of function and in the associated confidence I get from my approach and what I used to effect the function I wanted.

All this to say, that, if you are careful, purposeful, and build it properly, you are likely to enjoy reliable and positive use of your rail system.  That could be with soldering only ever other joiner and including a pair of feeders at every other pair of joiners that you do solder.

This is my My 2 cents

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Posted by modelmaker51 on Thursday, November 20, 2008 1:53 AM

I know it's "to each his/her own", but a drop for every section or two of track is way overkill if you'rer soldering your rail joints. Maybe instead people should be practicing their soldering skills more so they can have more confidence in their joins.

I have a 20 year old 12x23 double deck layout and my feeder drops are spaced every 10 to 15 feet without a single failure of a feeder or rail joint or voltage/current loss. The layout started out DC and for almost two years now is DCC with no changes in my wiring. My power buses and block runs (now districts) are 12 and 14 gage respectively with 20 and 22 gage feeders, some as long as 3 feet. There's a 5 amp booster for each level, (NCE system).I had 16 blocks to which I did add the auto light bulbs (thanks to Joe Fugate)

We run multiple long (50-75 cars) trains with multi-unit lash-ups, plus 2 branch lines and a yard engine or two all at the same time when my buddies are over, this includes several sound equipped engines. Thanks to the auto light bulbs, the very rare shorts are limited to the affected areas only.

Just wanted to share my method of madness. Practice your soldering so you don't have cold or brittle solder joins that can fail.

 

Jay 

C-415 Build: https://imageshack.com/a/tShC/1 

Other builds: https://imageshack.com/my/albums 

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Posted by rrinker on Thursday, November 20, 2008 7:39 AM

 I've had two varying experiences - and I believe quality of the track has a lot to do with it. To get a test loop up and runnign so I could install decoders, I picked up a bunch of Bachmann EZ-Track cheap at a train show. 22" radius and some straights. I built this into a basic 4x8 oval to run trains around to test them. I started with a single feed - trains very noticeably slowed on the far side, so I added another feeder to the halfway point. Train still slowed in the middle between the feeders, but not as bad as before. Based on this, and previous layouts, I planned to have a feeder to every section of flex track when I built the 8x12. My typical design was to solder two pieces of flex together along with a feeder for each corner curve. No other rail joints were soldered. When I had the first loop of track complete all the way around the 8x12, I hooked just one set of feeder to my Zephyr and trains ran with no slowdowns! 8x12 oval, the long straight sides mostly turnouts - ONE pair of feeders hooked up. All Atlas Code 83. I did still run a larger gauge bus and attach all the feeders. My intermediate feeders were every rail joiner - so a typical turnout had 3 pairs of feeders to it. Overkill? Maybe, but I built up masses of joiners with feeders at the bench and when I connected track I just used them instead of plain joiners, so it really wasn't extra work. I bet it would have worked for years with just that one pair of wires "two wires to the track" but eventually one of the intermediate joiners would have worked loose and I would have ended up with a dead section.

 I'm planning on handlaying track onthe new layout using PC board ties - so attaching feeders is trivial. I'll probably drop some every 3 feet or so. I'm not a fan of soldering EVERY rail joint, that's kind of asking for the track to kink if the humidity changes much, depending on your benchwork material. I definitely do not believe in soldering the joints to a turnout - if any piece of track is every going to give trouble and possibly require repalcement, it's a turnout. Since I didn't solder the joiners on mine, I could just push them back under the adjancent flex track and lift the turnout off.

Another benefit of lots of feeders - if you go back later and gap the track for signaling sections, if you have lots of feeders you have less chance of ending up with an 'orphan' section of track with no power to it - and each detection section will likely have multiple feeders. It would kind of stink to put a gap in the mniddle of a section that's say 10 feet between feeders only to find that the next rail joint north of the southernmost feeder was bad and the only reason it was working before the gap was that the power was coming from the other end... you now have on feeder driving say 8+ feet of track with lots of gaps and chances for failure.

                                            --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

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Posted by MRCProdigyrailroader on Thursday, November 20, 2008 10:08 AM

Can we just answer the man's questions?!

Btw I only have slowdowns because I have a 3.5 amp DCC system, and my layout may need some more feeders. If you run only a few feeders (My 2x8 switching layout/1st layout section only has 2, and I might need 1 more for a dockside siding) then normaly you should expect some issues with slowdown with that few amps.

The Master Hand!!! Modeling the modern BNSF and Norfolk Southern... On the same layout!!!
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Posted by CSX Robert on Thursday, November 20, 2008 10:45 AM
MRCProdigyrailroader
...Btw I only have slowdowns because I have a 3.5 amp DCC system, and my layout may need some more feeders. If you run only a few feeders (My 2x8 switching layout/1st layout section only has 2, and I might need 1 more for a dockside siding) then normaly you should expect some issues with slowdown with that few amps.
Actually, the amp capacity of your system has no bearing on your slowdown issues unless you are running near the limit of what your system can deliver. You could have a 1.5 amp system or a 10 amp system, and if you are only drawing .5 amps, your slow down will be the same. What does effect it is how much current you are drawing because the more current you draw, the more the voltage drop will be(V = I * R, where V=.voltage, I=current, and R= resistance). Because of this, you are actually more likely to have slow down issues with a more powerful system simply because you can run more trains(drawing more current) at the same time.
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Posted by MRCProdigyrailroader on Thursday, November 20, 2008 11:02 AM

CSX Robert
MRCProdigyrailroader
...Btw I only have slowdowns because I have a 3.5 amp DCC system, and my layout may need some more feeders. If you run only a few feeders (My 2x8 switching layout/1st layout section only has 2, and I might need 1 more for a dockside siding) then normaly you should expect some issues with slowdown with that few amps.

 

Actually, the amp capacity of your system has no bearing on your slowdown issues unless you are running near the limit of what your system can deliver. You could have a 1.5 amp system or a 10 amp system, and if you are only drawing .5 amps, your slow down will be the same. What does effect it is how much current you are drawing because the more current you draw, the more the voltage drop will be(V = I * R, where V=.voltage, I=current, and R= resistance). Because of this, you are actually more likely to have slow down issues with a more powerful system simply because you can run more trains(drawing more current) at the same time.

Must have been my track then, since I only have 2 feeders so far.

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Posted by Stevert on Thursday, November 20, 2008 11:46 AM

MRCProdigyrailroader

Must have been my track then, since I only have 2 feeders so far.

 

 

  Very likely so.  Nickel-silver has the advantage of not oxidizing rapidly, and unlike brass it's oxide is a conductor, so it's generally well-received for track (and deservedly so). 

  But compared to copper wire of the proper gauge, it's really not a very good conductor.  More info at Allan Gartner's excellent "Wiring for DCC" Web site:  http://www.wiringfordcc.com/trakwire.htm 

Steve

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Posted by MRCProdigyrailroader on Thursday, November 20, 2008 12:15 PM

Stevert

MRCProdigyrailroader

Must have been my track then, since I only have 2 feeders so far.

 

 

  Very likely so.  Nickel-silver has the advantage of not oxidizing rapidly, and unlike brass it's oxide is a conductor, so it's generally well-received for track (and deservedly so). 

  But compared to copper wire of the proper gauge, it's really not a very good conductor.  More info at Allan Gartner's excellent "Wiring for DCC" Web site:  http://www.wiringfordcc.com/trakwire.htm 

Steve

Then why not make brass or aluminium track, those 2 metals have better conductivity with the same benefits of Nickle-Silver, plus they don't sound like a type of battery. Think about it...

The Master Hand!!! Modeling the modern BNSF and Norfolk Southern... On the same layout!!!
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Posted by nbrodar on Thursday, November 20, 2008 12:45 PM

MRCProdigyrailroader

Then why not make brass or aluminium track, those 2 metals have better conductivity with the same benefits of Nickle-Silver, plus they don't sound like a type of battery. Think about it...

 

Track used to be brass.  Brass track oxides very quickly, and that oxide doesn't conduct like Nickel Silver does.  Aluminum is difficult to work with, and cannot be soldered, or mixed with copper wiring.

mobileman44

-  I've asked this before, but have to ask again to assure the I didn't misunderstand the answer.  Will Atlas code 100 turnouts (customline) cause the wheel shorts that I read so much about?  I ASSUME a dead frog would prevent this - or is it the other way around?

I have no problem with Atlas turnouts.  My layout is almost exclusively Atlas, in addition to a couple Peco curved ones.  So far I've had no problem with the Peco ones either.

mobileman44

- When you have a number of locos stopped on the layout (ie. in an engine terminal), can you turn them off with the DCC controller so as to reduce the layouts power consumption, or do you have to switch off the power to the tracks the locos are on?

My personal preference is to use on-off switches to isolate tracks in yards and engine terminals.  While not strictly needed, I don't like leaving hot decoders sitting around, and I still have a few DC locos left, shutting off the track eliminates the annoying beeping they make when receiving a DCC signal.  

I space my feeders every 6 feet or so.

Nick

 

Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/

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Posted by CSX Robert on Thursday, November 20, 2008 12:51 PM
Brass track actually used to be quite common. The problem with brass is that when it oxidizes, it's oxide does not conduct electricty. As Steve mentioned, the oxide of nickel-silver does conduct electricity. I don't know what dissadvantages there ight be to using Aluminum, but I'm sure there are some.

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