Can anyone tell me if this is a reverse loop?
Is a automatic reverse loop module needed if I am running dcc trains only....no dc(analog)?
Thanks
Nope.
A reverse loop allows the train to return in the opposite direction along the same path. With that diagram its not possible.
Good Luck
Jeremy
Nope, but I'm not familiar with all DCC systems either.
However most if not all DCC systems have a different address for each Loco, in which you program. In essence you can have muitiple locos controlled by one cab on one loop and have independent control over each. There are limits to the amout of cabs a single controller can handle. But yes you can run a train on either loop in either direction and have ful control without much more than a pair of feeder wires.
Another factor would be amps drawn, and if the unit can handle the amount of power necessary to move each loco.
Cheers
jlugar wrote:Alright then next question.....if I am running a 100% dcc setup with multiple trains on this track...do I need any insulators?
Possibly, You may need to put insulated joiners where your (4) crossovers are to eliminate a short circuit depending on the Make/Model of your turnouts.
Personally, I would put them in at the crossovers no matter what. I would also put Insulated Joiners between each pair of switches on the inner and outter loops, effectively giving you (4) individual "power districts" with their own "power feeders"(each end of each loop). You will never know there are insulated joiners there, and if you ever decide to install something like a Digitrax PM42<?>, (you can isolate any potential problems of shutting down the whole layout if you have a derail in one section in which the loco shorts between the rails), you won't have to take up any track to install the joiners later.
I see no NEED for insulators unless you plan to add detection later.
But you may WANT to add insulators for troubleshooting or future detection decisions.
Dave
Lackawanna Route of the Phoebe Snow
Hi, DCC would have nothing to do with needing insulators. The type of turnout would. If you have insulated frogs you are good to go. If you have live frogs you need to insulate the frog rails.
Tim.
timlange wrote: Hi, DCC would have nothing to do with needing insulators. The type of turnout would. If you have insulated frogs you are good to go. If you have live frogs you need to insulate the frog rails. Tim.
You are correct. I stand corrected. Mea Culpa!
If dcc has nothing to do with insulators then please explain more....I thought insulators generally were for 2 purposes, 1. To prevent reverse loop, and 2. To allow multiple areas to be powered seperately for analog train use. Since dcc trains do not need track power to be seperated in order to run more than one "dcc" train, I do not not see the necessity in using insulators except for diagnosing or prevent total shutdown due to short. Therefore when using a 100% dcc system I only see the need to use insulators when having a reverse loop. Also powered or unpowered frogs what would be the difference in a 100% dcc system.
Sorry for ramblin on.....But can someone explain in better detail if I am wrong, again, specifically in a 100% dcc system.
DCC has the ability to detect the presence of trains in a block and take action based on that. To do that, it must be divided into blocks. If you don't intend to use that capability, then you don't need blocks.
DCC can use detection blocks to operate track signals, or railroad crossing signals automatically. It can automatically throw a switch when a train is approaching it from the back side and it is set improperly, etc. On a large layout with a lot of trains, blocks allow you to divide it into separate power districts with multiple power supplies.
If you don't intend to do any of that stuff, you don't need blocks. With one big block, you can still run multiple trains independently, even in opposite directions on the same track.
jlugar wrote:roger that, I understand.....I think.....basically for a simple layout and design, I am correct in my theory. However the point is with insulators I can create seperate blocks and expand the amount of things that can be controlled via dcc.
WHOA!!!
Please see my first post first...
Then, to expand, or restate in a different manor, The control system has nothing and everything to do with Insulated rail joints.
In a DC system, you are correct in that insulated joints are used for controling "blocks" of track, as well as to prevent short circuits in a reversing loop. They are also used to prevent short circuits in other track arrangements, where not as obviously as a loop, the "current" can get "turned around". An example is at a "crossover", which you have (4) of in the plan you're asking about, where, as stated by someone else, if the frog is not "insulated" by the manufacture of the switch, YOU must insulate it by using insulated joiners, or slicing the rail forming a "gap".
This last senerio is pertinant to BOTH DC and DCC. Even DCC has a path the current follows (remember, even though it is Digital, it is still Direct Current ie DC). Even in DCC where you could have "just one big block" (if it were an oval with no switches), you still need to insulate, and isolate opposing polarity electrical current to prevent short circuiting the MUCH more expensive DCC system. Also, EVEN WITH DCC you need to have some way to "reverse" polarity in a Reversing Loop, be it a toggle switch or a Digitally Controlled Module, such as the PM42 I mentioned in the previous post.(( I am not try'n to push Digitrax products, you choose what will work best for you, but I use Digitrax, and it is what I am familiar with.)) The PM42 module I mentioned is capable of (in laymans terms) being a junction block that automatically reverses polarity when used on loops, and contains circuit breakers for its (4) outputs. By seperating your layout into "blocks" you will gain many advantages, that I can not nearly explain in one post, but as for operating-if using DCC-you will never know you have insulated "blocks". You do not need to flip this switch and that to make trains go.
As for PhobeVets post, He is for the most part correct that by "blocking" your layout, you can do much more in the future, IMHO your not there yet. Secondly, and sorry Pheobe if I hurt your feelings, but he is wrong about "not needing" to insulate at all if you have DCC.
The NEED to insulate is determined by YOUR SWITCHES. Are your switches 100% DCC compatable????? IF they are NOT, you WILL NEED to insulate those joints, or YOU WILL short out your DCC system. PERIOD!
I am truely sorry if I am coming across as try'n to know it all, or being cocky, or errogant, or even just irritated, but I truly hate to see someone mislead by misinformation.
I highly recommend you do some research (in books, websites and magazines-not asking others in forums) on your own, to learn for YOURSELF what YOU need for YOUR particular situation.
Thanks King!
Actually I have turned to forums for help because it seems to be the best way to find real case scenario help. Books and websites explain simple or typical situations but thing never really layout the simple way. And I will take with a grain of salt everything I learn from others and make my own assessment. But it is easy to see after reading everyones responses that it is a confusing subject, and I appreciate everyones help.
KingConrail:
Now that you have totally confused him, why don't you ask him what kind of switches he has or plans to buy. Most switches don't have live frogs.
I acknowledged yesterday that you were correct about having to isolate live frogs, so you are not offending me. I just think you are puting in too much detail and confusing a novice.
Phoebe Vet wrote: KingConrail:Now that you have totally confused him, why don't you ask him what kind of switches he has or plans to buy. Most switches don't have live frogs.I acknowledged yesterday that you were correct about having to isolate live frogs, so you are not offending me. I just think you are puting in too much detail and confusing a novice.
Phoebe Vet,
Let me start by saying that I truely respect your knowledge and opinions. I have come to find that your posts are generally informative and well written, making them very understandable. I want to also reiterate, I was not trying to offend you, or put you or your opinions/thoughs down.
I would ask that you re-read my last post. I believe that what I was conveying to the OP'r was very clearly written, and very to the point. I don't feel that what I was saying was at all confusing. Now I will acknowledge, I have been learning and using DCC for most of the time I have been a serious Modeler. I have never used DC control with "blocks", so maybe I am bias that generally speaking DCC is not complicated. Sure, the learning curve is much broader, and there are many more possibilities in DCC, (as I noted of your suggestion for "future" use of "blocking" for detection and signaling use).
If you have taken the time to re-read my post, I did ask if the OP's turn-outs/switches were 100% DCC compatable, which in this case is VERY relavant as he is using (8) of them. I will never consider myself an expert in this hobby because I know that I will always be able to learn something new, no matter how long I pursue this endevor. I do not consider myself a novice either, and I've had some experience with this issue. I want to pass along what I can to help this person avoid some costly mistakes that I have made.
My experience: I bought a couple Shinohara curved turn-outs at my LHS, that after researching, were supposed to be DCC compatable. The LHS owner/salesman knew that I was using DCC, and offered no input that this was not the case (I will note here, generally speaking, this LHS will give input, make suggestions, steer me away from a mistake). I installed them on the layout, looked them over twice (questioning what I learned compared to what I was seeing), and proceded to power up and test. ZAP!........Long story short, I nearly cost myself my brand new Digitrax system, because I didn't TRIPLE check my insulated joints. And, it turns out the switches that I purchased were "left over" stock, and not the newer DCC compatable switches that I intended to purchase and use. I acknowledge that "most" switches use insulated frogs, but NOT ALL, and that is an important factor.
I also would like to respectfully disagree with you that the information I provided was too detailed for the Posters experiance level. If the person learning is not provided with information that has substance (detail), how are they to learn from said information? Sure, I could have just given a YES or NO answer to their question, but what service would I be doing them other than simply giving an answer? My only intent was to be helpful, and pass on ( or pay forward) what I have gained from others, such as yourself, on this Forum, and in Litrature.
I hope that after all this, we can still be sociable. As I said in other words, You are an asset to this community, and I respect your input.
For the Original Poster, here is a link to a sight I was told about that has some very good information on DCC in general, and a section on just Switches. Wiring for DCC by Allan Gartner - Home (Index) Page
Hi, this is a response to no one in particular, but one thing was mentioned is one of my pet peeves. The term "DCC compatible turnout" I believe is a falsehood. Think about this, why would a command system care about a turnout? It doesn't! There are two types of turnouts electrically, live frog and insulated frog. A live frog has power to frog which will require an insulated gap on the frog rails to prevent a short circuit. This term DCC compatible came about due to some switches having poor construction that would create a short when a train ran through them. This short would occur whether DCC was used or not, but with DCC the short is noticeable due to the fast acting circuit breaker in DCC systems. If your track and wheels are in gauge you should not have any problems with quality turnouts.
DCC puts AC current on the rails, just like DC, still need to insulate both rails for reversing sections. DCC can control a non DCC loco by skewing the pulse one way or the other.
I use Shinohara on my railroad, my oldest installed turnout is about 15 years now and still works fine. I prefer a live frog and cut the needed gaps where I want them. Not saying Shinohara is the best, just saying they work for me, your mileage may vary.
King:
Let me apologize if I sounded like I was seeking an argument. That was not my intent. I was just trying to simplify.
I have been involved in training people in the workplace who have no pre existing knowledge of the subject being taught. One thing I have learned is that too much information presented at a time tends to cause people to lose focus, and feel overwhelmed. When that happens, the learning stops.
Everything you said was true. My position was that it was more than he needed to know at this particular time. His knowledge is obviously limited or he would have known he did not have a reversing section. Once we taught him that he didn't need to worry about reversing, I'm for not discussing that aspect any more.
Let me try a simpler approach to the live frog issue. What you said is correct, but it sounds complicated.
DC or DCC is irrelevant to this issue. A short circuit is the same for either.
The frog is the small odd shaped piece where two rails come together in the middle. On a switch that has a powered frog, the outside rails are always powered just like any other track. The two center rails, which are attached to the frog MIGHT be powered by the frog, and therefore will change polarity when the switch is thrown. They must therefor be insulated from the rail of the track section to which they are joined or they will cause a short on the side the train is not going to. If they are NOT powered by the live frog, then they get their track power from the section to which they are attached and Cannot be insulated or they will be dead. Most switches available in the local hobby shop have insulated frogs, in fact many of the frogs are plastic, and so it is not a problem.
Solution: ASK the person from whom you buy it if it has a powered frog and then act accordingly.
There is a good article in the magazine that has diagrams.
http://www.trains.com/mrr/default.aspx?c=a&id=185
Still friends?????
timlange wrote: Hi, this is a response to no one in particular, but one thing was mentioned is one of my pet peeves. The term "DCC compatible turnout" I believe is a falsehood. Think about this, why would a command system care about a turnout? It doesn't! (right, only because a Command Station does not have feelings) There are two types of turnouts electrically, live frog and insulated frog A live frog has power to frog which will require an insulated gap on the frog rails to prevent a short circuit. (Exactly true, as stated in most of the previous posts). This term DCC compatible came about due to some switches having poor construction that would create a short when a train ran through them. (WRONG! the term was coined in response to people believing that they did not NEED any insulated joints when using DCC, the whole intent of the disscussion on this thread.) This short would occur whether DCC was used or not, (not exactly true, in DC "block" control, the joints would be insulated, thus not causing the short circuit) but with DCC the short is noticeable due to the fast acting circuit breaker in DCC systems. (again, not exactly, the short is noticed because of the elimination of insulated joints, or "gaps", because again, SOME people think that DCC means no need for insulated rail joints) If your track and wheels are in gauge you should not have any problems with quality turnouts. (Completely irrelivant to the thread- we are discussing Electrical Continuity of various rail joints such as reverse loops and turn-outs, not operation of equipment over said rails. A wheel set out of gauge would not cause a short because one side or the other is insulated at the axle.) DCC puts AC current on the rails, just like DC, still need to insulate both rails for reversing sections. DCC can control a non DCC loco by skewing the pulse one way or the other.WHAT??? DCC is NOT Alternating Current (AC), it is Direct Current (DC), that is Digitally controlled.I use Shinohara on my railroad, my oldest installed turnout is about 15 years now and still works fine. I prefer a live frog and cut the needed gaps where I want them. Not saying Shinohara is the best, just saying they work for me, your mileage may vary. (I think you sum it up well...The NEEDED GAPS...when used with non-insulated frogs, as most of the previous posts in this thread have agreed apon .) Tim.
Hi, this is a response to no one in particular, but one thing was mentioned is one of my pet peeves. The term "DCC compatible turnout" I believe is a falsehood. Think about this, why would a command system care about a turnout? It doesn't! (right, only because a Command Station does not have feelings) There are two types of turnouts electrically, live frog and insulated frog A live frog has power to frog which will require an insulated gap on the frog rails to prevent a short circuit. (Exactly true, as stated in most of the previous posts). This term DCC compatible came about due to some switches having poor construction that would create a short when a train ran through them. (WRONG! the term was coined in response to people believing that they did not NEED any insulated joints when using DCC, the whole intent of the disscussion on this thread.) This short would occur whether DCC was used or not, (not exactly true, in DC "block" control, the joints would be insulated, thus not causing the short circuit) but with DCC the short is noticeable due to the fast acting circuit breaker in DCC systems. (again, not exactly, the short is noticed because of the elimination of insulated joints, or "gaps", because again, SOME people think that DCC means no need for insulated rail joints) If your track and wheels are in gauge you should not have any problems with quality turnouts. (Completely irrelivant to the thread- we are discussing Electrical Continuity of various rail joints such as reverse loops and turn-outs, not operation of equipment over said rails. A wheel set out of gauge would not cause a short because one side or the other is insulated at the axle.)
WHAT??? DCC is NOT Alternating Current (AC), it is Direct Current (DC), that is Digitally controlled.
I use Shinohara on my railroad, my oldest installed turnout is about 15 years now and still works fine. I prefer a live frog and cut the needed gaps where I want them. Not saying Shinohara is the best, just saying they work for me, your mileage may vary. (I think you sum it up well...The NEEDED GAPS...when used with non-insulated frogs, as most of the previous posts in this thread have agreed apon .)
I hope the red and blue highlighting makes things more understandable. This is a perfect example of Opinion over FACT.
To the original Post'r, I hope I have been of some help, but I am withdrawling from this thread at this time. I do not have the mental sanity to continue reading posts such as the above quoted.
Phoebe Vet wrote: There is a good article in the magazine that has diagrams.http://www.trains.com/mrr/default.aspx?c=a&id=185Still friends?????
It would be an honor to call you a Friend.
KingConrail76 wrote:(WRONG! the term was coined in response to people believing that they did not NEED any insulated joints when using DCC, the whole intent of the disscussion on this thread.)
I would have to disagree since anything having to do with the frog power is standard wiring that you have to do on any switch DC or DCC.
The term "DCC unfriendly" refers to the tendency for the switches to short out when thrown (which has ZERO to do with the frog). It is usually due to a set of contacts used to power the points and/or closure rails. Most of the articles on making turnouts "DCC friendly" involves removing those contacts, rebuilding the throwbar and points so they would not short out when thrown.
Dave H.
Dave H. Painted side goes up. My website : wnbranch.com
"WHAT??? DCC is NOT Alternating Current (AC), it is Direct Current (DC), that is Digitally controlled."
This statement is in error. While the power sent from the decoder to the motor is DC, the power and signal on the track is AC. Perhaps you were confused by the term "bipolar which refers to the fact that the digital pulse is mirrored on both the positive and negative side of the AC power. That mirroring would not be required if the pulses were on a DC power feed.
The AC power is what makes an analog engine buzz when it's not moving. It is the power to it's motor reversing.
Phoebe Vet wrote: KingConrail:"WHAT??? DCC is NOT Alternating Current (AC), it is Direct Current (DC), that is Digitally controlled."This statement is in error. While the power sent from the decoder to the motor is DC, the power and signal on the track is AC. Perhaps you were confused by the term "bipolar which refers to the fact that the digital pulse is mirrored on both the positive and negative side of the AC power. That mirroring would not be required if the pulses were on a DC power feed.The AC power is what makes an analog engine buzz when it's not moving. It is the power to it's motor reversing.
Though I Quoted this post, I also give Regards to CSX Robert.
I wish I could claim I was trying to keep things simple for the OP, but I can not. I quite honestly had forgotten that the Digital Signal that controls the DC power is infact AC (alternating current). Thank you both for correcting that error.
And as for the Post refering to Points vs. Frog, well I guess that I could have expanded on that previously as well. (I generally group Points and Frog together when speaking of electric continuity issues, as I have never had to solder feeders directly to any of my Points/Closure rails.) Having said that, I can now see that there could be a possibility of a short by an out of gauge wheelset, through the tread and flange of a single wheel.
As I have said in a previous post in this thread, I do not claim to know it all, but I guess I let my ego get ahead of itself. My apologies to all.
I know this is my second post since I said I was retiring from it, but the last few posts got me thinking I needed to re-learn what I thought I understood. I'm still reading myself, but found some information that may be helpful to some.
A quote from Wikipedia:
A DCC command station, in combination with its booster, modulates the voltage on the track to encode digital messages while providing electric power.
The voltage to the track is a bipolar DC signal. This results in a form of alternating current, but the DCC signal does not follow a sine wave. Instead, the command station quickly switches the direction of the DC voltage, resulting in a square wave. The length of time the voltage is applied in each direction provides the method for encoding data. To represent a binary one, the time is short (nominally 58µs for a half cycle), while a zero is represented by a longer period (nominally at least 100µs for a half cycle).
Each locomotive is equipped with a mobile DCC decoder that takes the signals from the track and, after rectification, routes power to the motor as requested. Power can also be routed to lights, smoke generators, and sound generators. A stationary decoder can be attached to the rails to allow control of turnouts, uncouplers, operating accessories (such as station announcements) and lights.
In a segment of DCC-powered track, it is possible to power a single analog model locomotive, by itself or in addition to the DCC equipped engines. The technique is known as zero stretching. Either the high or the low pulse of the zero bits can be extended to make the average voltage (and thus the current) either forward or reverse. However, because the raw power contains a heavy AC component, DC motors heat up much more quickly than they would on DC power, and some motor types (particularly coreless electric motors) can be damaged by a DCC signal.
...and the link to the article: Digital Command Control - Wikipedia, the free encyclopedia
Neither the Digitrax nor the NCE websites give this much technical info on just how DCC really works.
King Conrail:
I am a US Navy trained electronics technician.
Wikipedia is a collection of information provided by anyone who wishes to submit. It is not researched by the publisher.
This is from the Digitrax website: "Each bit is divided into two halves, which are "mirrored" around zero volts. The bottom half of the signal (below zero volts) is a mirror image of the top half, but shifted over half a bit width."
Above and below zero is the textbook definition of AC ... Alternating current ... The shape of the wave is irrelevant. Bipolar refers to the fact that the square wave digital signal is mirrored on both haves of the wave, rather than spread across the entire wave. All digital signals use a square wave. Digital recognizes only 1 and 0 which are represented by on and off. Analog can measure anywhere along the wave. If the digital signal was transmitted in DC the changes would be plus 14v and off. Because it is AC the signal changes from plus 14v to off to minus 14v to off, etc. By stretching only half of the zero bit, it can control a DC engine by sending the plus 14v part of the wave for a longer period of time than the minus 14v part or vice versa.
Interesting sidebar: Early airplanes did not have a throttle. They used an ignition interrupter which pilots called a blip switch to control power by shorting out the magneto, literally turning the engine on and off briefly. That is the same way DCC controls an analog engine.