Hi, I do not believe there is or should be a difference in wiring turnouts for DC or DCC. Electricity needs to flow correctly no matter what the control system. That said, I understand that turnouts that seem to work fine with DC may cause problems when used with DCC. I believe this is due to the momentary shorts caused by poor track work or wheel alignment or gauge. Using DC causes the wheels to spark and maybe a momentary slow down of the train. Whereas with DCC it may cause the fast acting circuit breaker to trip which would be very obvious!
I use Shinohara turnouts with DCC and I found that by checking track alignment (no kinks), and gauge of the track and wheels, I have trouble free operation. I run mainly steam, so I have a great variety of wheel sizes and aligments. Almost all my cars have metal wheels too. If I have poor trackwork I find it real quick!
Will a turnout work better with an isolated frog? It can be a quick fix that will stop DCC breakers from tripping, but the root cause is still there.
My DCC (Digitrax set at HO scale) puts out about 18 VAC, will that arc over a larger gap than 12 VDC?
A short on a DCC will have more current going through it, just because many DCC systems put out more current than DC controllers.
Thanks for listening to me,
Tim.
Ken:
See my post, with pictures, on how to permanently fix the Peco turnout frog short issue here.
Also, for a more thorough discussion of DCC and turnouts, you can read my post here.
Joe Fugate Modeling the 1980s SP Siskiyou Line in southern Oregon
gandydancer19 wrote: There have been some good answers to the problem so far, and I agree that the track or turnouts are not the problem.But now I think it's time to get technical. I have been an Electronics tech for about 40 years. (Navy trained) Now this isn't to say that I know more about electronics and DCC than anyone else. Just trying to let you know where my thoughts are coming from.Let's dispel the current myth first. Even though you have an 8 Amp booster, that does not mean that you are using 8 Amps. It means that 8 Amps is AVAILABLE for your layout. If you are only running two locos that are drawing 1 Amp each, you are using 2 Amps total, not 8. In this case you could use a 2 Amp booster and all would be well.Now to the problem. The insulation that is on the wire is a big contributing factor in it's melting. If the insulation was a high quality insulation, say Teflon, the insulation would not have melted. However, because the insulation is melting, and the insulation is probably an inexpensive type, the wire is heating up. OK, so this isn't news. Why is the wire heating up? 24 gauge wire with cheap insulation (Polyethylene) will only handle 3.7 Amps at 78Deg.F. Edit: Note that this is three times what a normal HO decoder should draw. (Sometimes our decoder wires are smaller than 24 gauge, but my book only goes down to 24 gauge wire.)(The same 24 gauge wire with Teflon insulation will handle a maximum current of 23.5 Amps at 78Deg.F.) (Previous figures are from a text that I have on wire and wiring harnesses). So that indicates a short somewhere from the truck pick-ups to the decoder. (Since most HO decoders are rated for one Amp, and the decoder is not burning out, it leads me to believe that the decoder is not drawing more that one Amp. from the loco motor.) Now if you squeeze or pinch an insulated wire, you decrease the insulation value of the insulation on the wire. So what this means is, if your decoder instillation is tight, you may be causing a short by pinching a wire to the loco frame, which may be the opposite polarity from the wire being pinched. The technical term for the unwanted current flow from a wire being pinched is called "Cold Flow". The easiest way to check this is to remove the shell of the loco, check the wires to make sure they are not being pinched somewhere, then run the loco under load without the shell and see if you can repeat the problem. Now, also notice that I mentioned 78Deg.F in some of the current figures above. If the temperature goes up, a lesser current flow will melt the insulation too. So a second contributing factor may be the buildup of heat in under the shell.Hope this gives you some ideas and things to check.
There have been some good answers to the problem so far, and I agree that the track or turnouts are not the problem.
But now I think it's time to get technical. I have been an Electronics tech for about 40 years. (Navy trained) Now this isn't to say that I know more about electronics and DCC than anyone else. Just trying to let you know where my thoughts are coming from.
Let's dispel the current myth first. Even though you have an 8 Amp booster, that does not mean that you are using 8 Amps. It means that 8 Amps is AVAILABLE for your layout. If you are only running two locos that are drawing 1 Amp each, you are using 2 Amps total, not 8. In this case you could use a 2 Amp booster and all would be well.
Now to the problem. The insulation that is on the wire is a big contributing factor in it's melting. If the insulation was a high quality insulation, say Teflon, the insulation would not have melted. However, because the insulation is melting, and the insulation is probably an inexpensive type, the wire is heating up. OK, so this isn't news. Why is the wire heating up? 24 gauge wire with cheap insulation (Polyethylene) will only handle 3.7 Amps at 78Deg.F.
Edit: Note that this is three times what a normal HO decoder should draw. (Sometimes our decoder wires are smaller than 24 gauge, but my book only goes down to 24 gauge wire.)
(The same 24 gauge wire with Teflon insulation will handle a maximum current of 23.5 Amps at 78Deg.F.) (Previous figures are from a text that I have on wire and wiring harnesses). So that indicates a short somewhere from the truck pick-ups to the decoder. (Since most HO decoders are rated for one Amp, and the decoder is not burning out, it leads me to believe that the decoder is not drawing more that one Amp. from the loco motor.)
Now if you squeeze or pinch an insulated wire, you decrease the insulation value of the insulation on the wire. So what this means is, if your decoder instillation is tight, you may be causing a short by pinching a wire to the loco frame, which may be the opposite polarity from the wire being pinched. The technical term for the unwanted current flow from a wire being pinched is called "Cold Flow". The easiest way to check this is to remove the shell of the loco, check the wires to make sure they are not being pinched somewhere, then run the loco under load without the shell and see if you can repeat the problem. Now, also notice that I mentioned 78Deg.F in some of the current figures above. If the temperature goes up, a lesser current flow will melt the insulation too. So a second contributing factor may be the buildup of heat in under the shell.
Hope this gives you some ideas and things to check.
Boy Elmer that was a great answer, as soon as my eyes un glazed I will read it again. 2 things we agree on for sure is that the engine will only draw as much as it needs. I could have a 200 amp booster and a engine only need .5 amp, that is all it gets. Plus the wire is way thin, and tightly packed so there is no cooling. Wires all so may have been pinched with the tight quaters I have to work in.
Other thing that more than likely will have no bearing, but from my racing days I was taught never to have spark plug wires run tightly together. It will create a magenet feild that will cause miss fires at a high RPM and or high load.
Mr Zepher, I will read your posting again and try to answer 1 by 1 like you did. Have yet to figuer out how to do that. But here is a try.
1. Weight is not a problem. All engines I listed could still spin the wheels, so that should not have caused a over load of the motor.
2. Not sure if this was your question, but train the Dash 9 was draging is a easy puller. But, when the Dash 9 smoked it was on the C-Line that is a work in proggres. It could have picked up a spike or some foam. With it being in the tunnel, I could no see it stall. It could have been in there for 20 seconds or 20 minutes.
3. Checking the turn outs. I still think that is the problem! Reason I say that say a year ago I install Peco turnouts to the engine yard. Few of my engines would arch when going throught the yard or past the turnouts that went to the yard. PK2 E-6 was one of them, and i was still DC at that time. I could see a spark when it passed over that spot. I used a quick fix that I was told about here on the site. Nail polish betten the rails where the spark happen. Come to think of it, last time I used the nail polis was around a year ago as well.
Now that I am DCC, I have not seen sparks, plus I am using rail cleaning cars. By now there is no nail polish left. I will check for tail tell sighns of arching. New section, C line where the Dash 9 smoked has no Peco turnouts installed yet. But, all engines I have had problems listed have seen 98% of there time on either the A or B line.
If some kind person would post PIC's of the proper way to install DCC turnsout it may help end this posting and help others later.
Plus thanks for all your thoughts and time to answer this questions as well. If you remember me from when I joined this great site, I have came a long way but still have some to go before I become a master.
Cuda Ken
I hate Rust
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
cacole wrote: The burned wires are an indication that you're overloading the engines by trying to pull a too heavy train for too long, and has nothing to do with the power booster's output, turnouts, track shorts, track wiring, or anything else. You're simply overloading the engines and drawing too much current through too light a gauge of wiring. You're lucky the decoders haven't been burned out.
The burned wires are an indication that you're overloading the engines by trying to pull a too heavy train for too long, and has nothing to do with the power booster's output, turnouts, track shorts, track wiring, or anything else. You're simply overloading the engines and drawing too much current through too light a gauge of wiring. You're lucky the decoders haven't been burned out.
I'd agree and disagree!
The wires/insulation are burning because they are gettin gtoo hot, because there is too much current being drawn for those wires. In a stock loco/decoder combo, I would say that if this happens, the wire used was not heavy enough, not that the Ken is pulling too much. My opinion would be that the manufacturer should use wire heavy enough to carry the current the loco can draw before it slips or stalls.
Now, in the case where Ken added weight to the loco, it's hard to blame the manufacturer as much. In this case the original wire may have been heavy enough to carry the current the motor could draw before it slipped, but by adding the weight, Ken increases this, since it can come closer to stalling than slipping.
Jeff But it's a dry heat!
cudaken wrote:My bench started as DC, I have feeders about ever 12 feet and they are 16 gauge. Main bus line is 12, gauge wire. I am using a Bachmann EZ Command with an 8 amp MRC power station. I have apx 250 feet of rails, broken down to 3 main lines.
In most cases, well over 100 hours some 200 hours. I may have just, wore them out.
Plus all have pulled pretty long trains up a 1.5% grade. I do push what they can do and more than one has stalled because of to heavy of a load.
It is all so not uncommon for them to run 2 hours none stop!
If you think it is the way I have the turnouts installed could you post a picture of the way they should be installed?
I have no answer for you. The only time in 40 years I've melted down a wire inside the locomotive was when there was a short circuit inside. I was running a locomotive that the decoder got so hot it melted the solder and all the components fell out on the rail. However, I do know that this is what ended the world record endurance run for a model railroad locomotive.
Ok I thought of two more questions. How often do the trains switch from loop to loop? Are you certain there are no DC power packs still connected to the rails (even if they are turned off)?
modelmaker51 wrote:I'm still learnin' this DCC stuff too, but my first thought was the 8 amp booster maybe too much oomph for the size layout and the problem seems to be occurring with track "input" wires, also, if there are any mini shorts at any of the turnout frogs, repeated shorts over a couple of hours of running would heat up the weakest point in the whole cicuit which would be those wires. Or am I way off base here?
If the short is in the frog, the current shouldn't be getting to those wires, in theory. Though I never liked the idea of the mondo booster! Some taillights might help.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
That's why I think the RRAmpmeter would be handy. The black wires and burned out board came from a lot of current, but was it a single event, or was it a consistently high draw?
Vail / Jeff, thank you for your kind answer. I'am tired of the you are stupid answers I get from some folks here. I spoke with Dave from Athearn today, (about the RTR Dash 9) he as well never heard of such a problem. But to his and Athearn's credit they are sending me a new board for free. Took the Dash 9 to K-10 Model Trains in Maryville IL, best LHS you could hope to have I will add. Ken, the owner and few of the other customer all so could not figuer out what happned to the RTR Dash 9 that burnt the wires.
A further thought...
For you, a RRAmpmeter from Tony's might be an exceppent idea. It would be nice to know how much current is really beign drawn. It might make a lot of things clear.
Hmmm, I don't think the things you are seeing have anything to do with the turnouts, or even the alyout wiring.
The wiring inside the locos is very light. I think in a lot of cases it is too light, but they are expecting to get a way with it, since most people won't run the locos as hard as you are. I get teh feeling that there is little or no design margin being built in. So, when you run, pulling a heavy load, for a long time, the wires get hot. The a little insulation burns off, and you get a short, or a near short. At that point, you 8 Amp booster has plenty of power to cause a total meltdown.
Solution? Well, when possible, you probably need to use heavier duty decoders. And heavier wire, as you did in the FP-45. There you moved the problem from the wire, to the decoder. Agai, I think the decoder manufacturers are working on the edge, and your mode of operations may be pushing them past it.
My bench started as DC, I have feeders about ever 12 feet and they are 16 gauge. Main bus line is 12, gauge wire. I am using a Bachmann EZ Command with an 8 amp MRC power station. I have apx 250 feet of rails, broken down to 3 main lines. C-Line is free standing at this point. Later it will be connected to the A-Line, but now it is its own loop. I have around 30 turnouts, about a 25% are Peco with Insulfrog's, 75% are Atlas Custom's and rest are older Atlas that came off E-Bay and they are #6's.
All the turnouts that connect the A line to the B line have two plastic rail joiners. Turnouts that are for one line only do not have plastic joiners. I have 3 power blocks that the booster feeds to. Polarity's, are correct.
Bench runs fine, no dead spots or derailing problems.
Now the problem, I either have real bad luck with the engines I buy, or there is a gremlin lurking on the bench.
Main problem I am finding is power wires from trucks to decoder board are getting hot and starting to melt. All the engines I am getting ready to list have a lot of run time. In most cases, well over 100 hours some 200 hours. I may have just, wore them out. Plus all have pulled pretty long trains up a 1.5% grade. I do push what they can do and more than one has stalled because of to heavy of a load.
1. PK2 E-6, melted power wire to the, decoder board. Not through but bubbled up. It is the only engine that has ran DC only and pulled 60 cars. Still runs.
2. Older Athearn Blue Box FP-45. I converted it to DCC using an Athearn RTR Dash 9 motor and decoder board. I used a heaver wire than what the RTR engines came with I think I used 18, gauge. One of the printed circuits burned out where the power lead, hooked too.
3. Athearn RTR Dash 9, see posting "letting the smoke out".
4. Blue Line GE AC 6000, lost power pick up to the front truck. It was replaced under warranty so I do not know what the problem was.
5. BLI M1-A, steam engine. I could not keep it wheels clean, so I thought. Last night I flipped it over and had power pickup from the tender but not the engine. Power wire from the engine to the tender was melted as well! Of all the engines I have listed, this is the one that was beaten on the most. Well over 200 hours and dragged heavy loads. I have cracked and replaced to sets of center gears to give you an idea.
Other problem, which I think is common to other people, is the decoder CV's like to change.
If you think it is the way I have the turnouts installed could you post a picture of the way they should be installed? I am still weak on the names of the different parts of a turnout.
Thanks for reading what I think is my longest posting yet and looking forward to the answer and coming questions.