What is the difference between DC and DCC?
I'm certainly not the resident expert on DCC, or DC, nor am I an expert at explaining the differences, only what I know from my experiences, and slow climb up the DCC learning curve.
If nothing else, this "bump" in your post will get some attention from those that can explain it so it's more understandable.
With DC, (direct current) your locomotive responds to a power pack/throttle, and nothing more. You have few options, unless you have a really sophisticated DC wiring and control system.
You can run one train, and to run more than one train, requires a system of power control "blocks".
With DCC, (digitam command control) you actually operate your train with a series of commands, that the locomotive responds to.
You can run more than one train, because each locomotive has it's own "address", so multiple train operation is possible, with out all of the specially wired control blocks.
I guess thats the basic, as well as I can explain it. I'll step aside and let the more knowledgeable explain it to you.
There is tons of reading material out there, along with web sites, that can spell it all out for you.
Mike.
My You Tube
Probably the simplest way to think of the difference is that in DC you're controlling the track, in DCC, you're directly controlling the locomotive.
If you take a say a 3' section of flextrack and hook it up to DC and put 3 engines on the track, when you apply power all will move, and all will move in the same direction (unless one engine's motor connections were hooked up backwards!).
In DCC, each engine has it's own decoder, so the engine only responds to commands from the DCC system addressed to that particular engine. With the 3 engines on the 3' section of track above, if you hook the track up to a DCC system, you can call up just one engine and move that one (or turn the lights on and off, or blow the horn etc.) while the other two do nothing.
Of course, in DCC, if you have multiple controllers (like say handheld throttles) you can have all three engines respond to a different throttle, so three people can each run one engine independent from the others.
The main difference for the user is with DC you can only run one train on a certain track, while with DCC you can run as many as you want. Now I’ll go into a bit more detail...
DC works we’re there is a power pack that outputs voltage at about 16 volts. Now on DC the voltage changes in order to control the speed of the loco, to more voltage, the faster the train moves. The reason you can’t control more than one engine at a time is the only way to control a loco is through the voltage, and that will apply to any loco on the powered track. Now some people will divide their DC layouts into “blocks”, and you can switch these blocks between you powerpacks to run multiple trains. This is a bit complex and and I don’t really get it. If you want I’m sure other forums members can give you a more detailed response should you like more info.
Now DCC doesn’t run like DC, the track is always powered at a constant voltage. The way you control the engines is by sending ”packets“ of digital signals to a ”decoder”, a small computer chip in the loco that accepts the DCC signals. (Again I am far from knowledgeable about how this works, but other likely are.) Now with DCC each packet can go to a specific loco, and so multiple locos can be run on the exact same track with no fancy wiring. Now with DCC you can also individually control lights and SOUND! This is one advantage you get with DCC over DC (okay, there are ways to get this in DC, but that’s more advanced).
Now there are many advantages and disadvantages for each system, and everyone will argue will argue one way or the other , but that’s the basic differences. Hope it was helpful.
Regards, Isaac
I model my railroad and you model yours! I model my way and you model yours!
Read the link. Simple explanation. Related topics in the link. Save the link.
The DCC controller is an encoder. The loco has a decoder to interpret what the encoder is telling it what to do.
https://sites.google.com/site/markgurries/home/technical-discussions/dc-versus-dcc-bacground
I have a NCE Power Cab for some years but can easily unplug and plug in the DC power pack for measuring DC current for DCC mods but have not done that in a few years.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
To run multiple trains simultaneously on DC, you need multiple power blocks, and you need to always be aware of your block boundaries. This can be difficult on a small layout because the blocks will be short. DCC does not have this limitation which in some ways makes it superior for smaller layouts.
When I put my first DCC decoder in and ran a train for just a little while, I unplugged my old DC power pack and never went back.
It takes an iron man to play with a toy iron horse.
Hello All,
Start here...NMRA
Hope this helps
"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"
I and a lot of people my age I know just never went into DC at all, DCC has just always been the more convinient system to use. If you have a decent knowledge of computers and some basic info on coding or wiring DCC is really intuitive, and the wiring/coding is not to far complex to learn for it for those who have never touched it before.But DCC comes with a price... Expect to pay $50-$100 MORE per locomotive with DCC, and get used to buying expensive controlers etc. I personally think its worth it, and can't imagine the hobby without it... but I know a lot of people prefer the lower cost method to old school DC. Remember a lot of old DC locomotives are what you see for sale in train shows and estate sales, so its a lot easier to build up a fleet of them. Lot of manufacturers still offer DC locomotives to. Just remember that to run more than one train on DC requires wiring blocks and control systems to allow you to control each stretch of the layout. If your looking into an entry level layout with only one or two trains, DC ain't a bad place to start... just remember that if you want to go to DCC later that DC equipment will need to be upgraded via installing decoder chips before you can use them on DCC systems.
Why hello! and welcome to the MRR forums, the one stop answer to all your questions and some extra answers/comments free of charge! (what sales pitch is good without free stuff?)
Anyway, to answer your question, DCC is AC current pumped through your tracks at an almost constant 14 volts, while DC is a controller that pumps a varying amount of voltage in depending on how for you have the knob turned on your controller. If you have pockets of any tolerance, go for DCC. You will never regret it, and I may go so far as to say that I would recommend NCE for your system of choice. Very budget and beginner friendly. Hope all of this helps!
I'm beginning to realize that Windows 10 and sound decoders have a lot in common. There are so many things you have to change in order to get them to work the way you want.
MisterBeasleyTo run multiple trains simultaneously on DC, you need multiple power blocks, and you need to always be aware of your block boundaries...
While I agree with that, in my opinion, you also need multiple operators - one for each train. While one person can run multiple trains with DCC, it seems to me to be better-suited to still have an operator for each train. Otherwise, it's like turning on a TV in every room of the house, but watching the set in only one of those rooms.
To that end, if you belong to a club, or host operating sessions with friends, DCC would be the route to choose.DCC is also a good choice if you want sound and lights, too, even for a lone wolf modeller.
I'm using DC, and can run multiple trains on my layout if I so choose - no blocks, no buttons to push or switches to flip, just multiple trains chasing each other around the layout, perhaps even catching-up with others. Not something I would normally do, unless I were entertaining my grandkids, and the ones who are interested would rather run a train on their own.I have never understood the desire for a sole operator, whether using DC or DCC, to run two (or more) trains at the same time, when they could reasonably enjoy and operate, in a controlled manner, only one of them at a time. While I have a medium-size layout that could probably support 3 or 4 operators were it DCC, it's not a part of the hobby I would enjoy, and I wouldn't even entertain the thought of doing it with block control in DC.
As for sound and lights, they're beyond my interests, too. I have operated on the layouts of friends using DCC, and am impressed by some aspects of the technology, but they're outside my personal interests in regards to my own layout.
DC and DCC each have their own pros and cons, which, I think, will vary depending on the individual. For this individual, the pros for DC, simple wiring and low cost, outweighed anything that DCC offered for my situation.
Wayne
The replies to these threads are always interesting......
And in my opinion, so far, it is interesting that the most insightful response has come from the lone wolf DC operator, Dr Wayne.
It is hard to know the prespective of the OP, making it hard to offer more than basic technical info, as some of you have done.
In my mind, Dr Wayne's points are compelling:
Each train requires its own operator, DC or DCC does not matter.
If you want sound and advanced lighting, you want DCC, no matter your other goals.
My own additional thought about one operator running multiple trains is that type of display running requires dedicated loops of track no matter the control system.
After that it gets complex as to the virtures and vises of each system.
Misinformation - DC is 16 volts, sorry no it is not. NMRA Standards and Recommended practices have always set 12 volts as the bench mark full speed voltage, with 16 volts being a maximum tollerable no load voltage.
Those who understand how transformers work, and who understand the design of power supplies, both simple and advanced understand that a basic power supply will read a much higher voltage under a no load condition than it will at its rated current.
It is these no load readings of inexpensive power packs that give some the impression that DC voltage is 16 volts or even more.
For many DCC is the best choice. But for those who clearly understand both systems, and clearly understand their own personal goals, DCC may not be their best choice.
I have hundreds of operational hours on several large DCC layouts, I have designed track plans and help construct some of those layouts. I know how DCC works......
Yet I do not use it on my own layout.
Instead I use a very complex form of DC called Advanced Cab Control, of which there are numerous variants.
It suits my goals better at a lower cost without investing time or money in features I do not value.
It provides an impressive list of features:
Wireless radio throttles for walk around control.
Full signaling and CTC control with ATC (automatic train control) safety features.
Single button route control of turnouts with working signal interlocks.
Simple operation requires only using five buttons on the handheld controller.
It does not provide for:
Onboard sound.
Seperate/elaberate lighing control.
My advice, learn more and decide what you like and want to do before you spend too much in any direction.
Sheldon
Thanks for your input, Sheldon, and for your kind words.
ATLANTIC CENTRAL....My advice, learn more and decide what you like and want to do before you spend too much in any direction.
While I was trying to convey the same advice, your version is much more to the point and easier to understand.
And lest anyone think that I'm anti-DCC, I'm not...it simply doesn't offer anything to me that I want and I don't already have.
"Versus" in the title is misleading........the question is "what is the difference.....?"
As someone who has 11 years DCC and 40 of DC (also 5 of AC), I can say the difference is simple......DC operates the tracks, DCC operates the locomotives.
That said, I strongly recommend getting a couple of the Kalmbach beginner books on wiring, DCC, etc. before committing to either one.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
To me, the question is too basic to justify the extensive answers being offered in reply. If one simply Googles, 'DC versus DCC', a quick search would not only get the answer, but it would produce plenty of answers. If it were me, I would start there.
Alton Junction
The exact answer has been stated several times. DC, you drive the track, DCC, you drive the train.
Starting from scratch, there's little reason to go DC. Unless you are only building a simple loop around the tree.
Have an extensive collection of locos? 100 or more, or many of older vintage that aren't so easy to convert to DCC? Then yooou need to think about things and how you want to proceed.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
drcook What is the difference between DC and DCC?
With DC, to control more than one train on a layout, you have to control the tracks - by dividing sections of track into into electrical blocks, which feed power from more than one power pack.
On a good sized layout, it may not be uncommon for someone to say "who's got my train" because they selected a block with your train in it for their cab/power pack.
With DCC, you control trains by their address, and not the track.
Rio Grande. The Action Road - Focus 1977-1983
riogrande5761 drcook What is the difference between DC and DCC? With DC, to control more than one train on a layout, you have to control the tracks - by dividing sections of track into into electrical blocks, which feed power from more than one power pack. On a good sized layout, it may not be uncommon for someone to say "who's got my train" because they selected a block with your train in it for their cab/power pack. With DCC, you control trains by their address, and not the track.
And at our club, sometimes you still yell "who's got my train" because after all these years, people still can;t figure out that if their loco is 564, they need to put the numbers 564 in the throttle they are holding to control it, not 714. Sorry Dave, I think you will be herding cats at your club for a long time to come, even if they at least stop running into one another.
rrinker riogrande5761 drcook What is the difference between DC and DCC? With DC, to control more than one train on a layout, you have to control the tracks - by dividing sections of track into into electrical blocks, which feed power from more than one power pack. On a good sized layout, it may not be uncommon for someone to say "who's got my train" because they selected a block with your train in it for their cab/power pack. And at our club, sometimes you still yell "who's got my train" because after all these years, people still can;t figure out that if their loco is 564, they need to put the numbers 564 in the throttle they are holding to control it, not 714. Sorry Dave, I think you will be herding cats at your club for a long time to come, even if they at least stop running into one another. --Randy
riogrande5761 drcook What is the difference between DC and DCC? With DC, to control more than one train on a layout, you have to control the tracks - by dividing sections of track into into electrical blocks, which feed power from more than one power pack. On a good sized layout, it may not be uncommon for someone to say "who's got my train" because they selected a block with your train in it for their cab/power pack.
And at our club, sometimes you still yell "who's got my train" because after all these years, people still can;t figure out that if their loco is 564, they need to put the numbers 564 in the throttle they are holding to control it, not 714.
Sorry Dave, I think you will be herding cats at your club for a long time to come, even if they at least stop running into one another.
So choose wisely young padowan.
rrinker riogrande5761 drcook What is the difference between DC and DCC? With DC, to control more than one train on a layout, you have to control the tracks - by dividing sections of track into into electrical blocks, which feed power from more than one power pack. On a good sized layout, it may not be uncommon for someone to say "who's got my train" because they selected a block with your train in it for their cab/power pack. With DCC, you control trains by their address, and not the track. And at our club, sometimes you still yell "who's got my train" because after all these years, people still can;t figure out that if their loco is 564, they need to put the numbers 564 in the throttle they are holding to control it, not 714. Sorry Dave, I think you will be herding cats at your club for a long time to come, even if they at least stop running into one another. --Randy
My local club bullt in the early 1980's had fourteen blocks in two rooms. Four throttles. A control panel with one fellow to control blocks. If he got to talking, we heard that cry almost every operating session.
With DCC, no more.
richg1998 rrinker riogrande5761 drcook What is the difference between DC and DCC? With DC, to control more than one train on a layout, you have to control the tracks - by dividing sections of track into into electrical blocks, which feed power from more than one power pack. On a good sized layout, it may not be uncommon for someone to say "who's got my train" because they selected a block with your train in it for their cab/power pack. With DCC, you control trains by their address, and not the track. And at our club, sometimes you still yell "who's got my train" because after all these years, people still can;t figure out that if their loco is 564, they need to put the numbers 564 in the throttle they are holding to control it, not 714. Sorry Dave, I think you will be herding cats at your club for a long time to come, even if they at least stop running into one another. --Randy My local club bullt in the early 1980's had fourteen blocks in two rooms. Four throttles. A control panel with one fellow to control blocks. If he got to talking, we heard that cry almost every operating session. With DCC, no more. Rich
And yet I can build a DC system were it is impossible to over run the block or blocks assigned to you. And guess how much extra it costs? Zero, zip, nada, not one penny.
How you ask? You really don't want to know, because you are happy with DCC.
And most people should use DCC, for a number of reasons.
But few of those reasons have to do with the common reasons given against DC.
How about we sell DCC based on its features and benifits rather than miss information on the limitations of DC?
The unfortunate truth is most people in the hobby today have never seen or operated on a well designed DC system, yet they are all "experts" on what is "wrong" with DC.
Prototype jobs:
Engineers: control locomotives
Conductors: control trains
Dispatchers: control railroads - by controlling the tracks those other two people must use
DCC does that first job the best, no question.
DC can simulate that last job just as well as DCC..........usually for a lot less work and money.
But again, I realize few people with model trains are really interested in prototype operation.
But again, to new people I always say DCC is likely your best choice, especially if you like sound.
Get ready for a lively discussion about the differences. I've done both and converted to DCC. It was a fun learning curve to climb. You also had to pay a larger upfront cost with getting the power cab, throttle, etc.
I love DCC. Once you know how to attach the feeders, you go slowly and constantly checking. DCC requires a bit more accuracy.
kasskaboose Get ready for a lively discussion about the differences. I've done both and converted to DCC. It was a fun learning curve to climb. You also had to pay a larger upfront cost with getting the power cab, throttle, etc. I love DCC. Once you know how to attach the feeders, you go slowly and constantly checking. DCC requires a bit more accuracy.
Now that's a new one? Requires a bit more accuracy? I would love to hear that explained.
By the way, if I did want to use DCC, it would be from this company:
www.cvpusa.com
It still gets back to each person's goals for their modeling, one size does not fit all.
ATLANTIC CENTRAL The unfortunate truth is most people in the hobby today have never seen or operated on a well designed DC system, yet they are all "experts" on what is "wrong" with DC.
So if you have to see and operate on a well designed DC system, and so many haven't, there lies the problem. You have to and so many haven't. That tends to make them "experts" in a practical way - meaning they know what they don't know and maybe don't need to know. That isn't a bad thing necessarily.
Prototype jobs: Engineers: control locomotives Conductors: control trains Dispatchers: control railroads - by controlling the tracks those other two people must use DCC does that first job the best, no question. DC can simulate that last job just as well as DCC..........usually for a lot less work and money. DC can simulate that last job just as well as DCC..........usually for a lot less work and money.
Bingo, which is probably why DCC has gotten so popular.
That isn't necessarily a bad thing. There can be a point for some where getting "realistic" becomes "work" and not so much fun. Many are in the hobby for fun and relaxation and like to simulate train operations to some degree without it becoming too laborious or tedious. In otherwords, different strokes for different folks. It depends on what your poison is.
But again, to new people I always say DCC is likely your best choice, especially if you like sound. Sheldon
And old people too.
I run a layout that has no blocks, only Peco power routing turnouts. I do run multiple trains in plain DC--that is when things can get exciting--keeping trains from running into each other--but it can actually be done. You do not have to have block control or fancy wiring. One must pay attention to where each train is and the speed. One does not have to have DCC to do this; one must only be attentive to what is going on.
I'm 51 in two weeks, have tried DCC and sound but was always underwhelmed, and I have some models that I don't want to deal with disassembling to convert to DCC, including Overland Models diesels.
John Mock
You can have two or more trains running at one time in DC without using blocks, but you can't control each one separately. With a large enough layout, you can have one train following the other and if there speeds are similar (which is easier to do in DCC than DC) the trains will be OK. But with no blocks, if you stop one train, you stop both. (BTW if you're using power routing turnouts to create sidetracks so you can put one train 'in the hole' so another can pass, you are using blocks.)
Cost-wise, I think the issue is bigger if you start in DC and have a fleet of 10-20 engines and then decide to convert to DCC. It is easier if you're starting from scratch to just go with DCC. A DCC system from CVP or NCE with two controllers built into it costs about the same as two good, new DC powerpacks and the toggle switches you'll need to divide the layout up into blocks. If you're not interested in sound, good regular decoders can be bought for around $20, maybe less if you find a sale or buy in bulk. Micro-Mark catalogue usually has sound/DCC-equipped engines selling in the $110-160 range.
The other thing that DCC does well (and it's not often mentioned on these discussions about DC & DCC) is constant lighting and lighting-effects.
I've never cared for the unrealistic non-constant lighting of DC. In order to make the headlight turn on you have to increase the voltage to the track; thereby requiring your locomotive to be in motion for the headlight to light up. And, as you slow down, the headlight gets dimmer and dimmer until it goes out completely.
Because DCC is constant voltage, I can have the headlight come on full-strength as my locomotive idles away in the yard or trackside. With Rule 17 programmed I can also have a dimmed headlight brighten when starting off or dim again after coming to a complete stop. I can also have the opposite headlight dim when going from forward to reverse back to forward again.
I can create mars or gyralighting effects and play with the flash-rate. To me - that's a LOT more fun than sound and something I don't feel the need to "mute" should I get tired of it.
While the above could be utilized with DC using circuit boards and caps, it's already suited for and integrated into a DCC decoder. But...if lighting isn't important to you, or the operation of your layout - it's a moot point. I thought it worth adding to the discussion, nonetheless...
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
You CAN do constant lighting with DC, but you MUST use a pulse, preferentially a PWM, DC power pack.
I ired up some stuff for another member of the old club I belonged to. We had 2 power systems, the big MRC walkaround one and the CMI similar system. The two ran trains simialrly, but they used different types of pusle power - on one main, the constantly lighting circuit worked great, loco standing stilla nd the headlight would still be on. On the other track, connected to the other power supply - nada. All because one supplied pulses with enough amplitude to charge the capacitor in the constant light circuit, and the other one did not.
In theory, the green lightboards that engines started to come with in the 1990's were supposed to allow for constant lighting, by causing the first say 1.5 volts of DC power to go to the lights, and then only anything more than that to go to the engine. Except for making the engine run slower than a similar engine without a lightboard, I never saw that it really had any effect.
BTW re sound...I suspect the future of sound is going to move away from sound and speakers being in the engine, and towards being in the controller - kinda like Bachmann's "EZ-App" system. You can use a phone or tablet to run the engine, and the sound (if you want it) comes from the phone.
I bet pretty soon DCC manufacturers will offer something similar, with a speaker and a headphone plug built into a walk-around device. I think you could get into "virtual reality" sound. So for example, the closer you are to the engine, the louder the engine sounds in the headphones or speaker. You may be able to make it so that with headphones, if the engine is to your left, the sound is louder in the left earpiece. Plus, you could have proximity-based background sounds running, like street sounds in the big city on the layout, mooing when you're near the dairy farm, etc. I'd think a lot of it could be done now with transponding DCC technology?
tstage The other thing that DCC does well (and it's not often mentioned on these discussions about DC & DCC) is constant lighting and lighting-effects. I've never cared for the unrealistic non-constant lighting of DC. In order to make the headlight turn on you have to increase the voltage to the track; thereby requiring your locomotive to be in motion for the headlight to light up. And, as you slow down, the headlight gets dimmer and dimmer until it goes out completely. Because DCC is constant voltage, I can have the headlight come on full-strength as my locomotive idles away in the yard or trackside. With Rule 17 programmed I can also have a dimmed headlight brighten when starting off or dim again after coming to a complete stop. I can also have the opposite headlight dim when going from forward to reverse back to forward again. I can create mars or gyralighting effects and play with the flash-rate. To me - that's a LOT more fun than sound and something I don't feel the need to "mute" should I get tired of it. While the above could be utilized with DC using circuit boards and caps, it's already suited for and integrated into a DCC decoder. But...if lighting isn't important to you, or the operation of your layout - it's a moot point. I thought it worth adding to the discussion, nonetheless... Tom
Tom, constant brightness headlights have been pretty standard on all but the least expensive DC locos for 20 years or more now.
And, as Randy pointed out, they work even better with Pulse Widith Modulated power.
With my PWM Aristo Train Engineer wireless throttles, my headlights come on full brighness way before the loco moves, in fact you can leave the loco sitting still with the lights on. Then as you accelerate the lighting stays constant at all speeds.
OK, if you model modern times with ditch lights and what not, I get it. But in 1954 many roads had just started turing lights on in daylight, and just started experimenting/adopting with Mars lights.