DC or DCC???
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Hello.
I suppose the easiest way to explain it is.
In DC you drive the track.The more you turn the control knob the more voltage you put on the track & the faster the loco will move.If you have two locos on the track then they will both move.
In DCC you drive the locomotive.There is always full voltage on the track.
Each locomotive has its own individual address number which you can change if you wish.You punch in the number of the locomotive you wish to operate & only that loco will move. You can have as many locomotives you wish on the same track but only the locomotive you select will move. All the others will stay exactly as they are until you decide to select one of them by dialing in its number on your controller. This is achieved by putting a small DCC decoder in each locomotive so a locomotive will only move when you select its address.If you want to read all about DCC then grab yourself a large coffee & read here.
http://www.dccconcepts.com/index_files/DCCadvice1.htm
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Well, I'm probably going to goof this up a little bit, but........ DC sends voltage down the track. + on one track, - on the other. Everything works off of switches.
DCC sends out pulses that the decoders can read. Every decoder has a different address that is decoded through these pulses going through the track.
Some people like the old school DC stuff, and have very nice setups using this. I started later on when DCC was established, and I bought all DCC stuff with a bunch of decoders for everything. I don't regret it.
If you started the hobby with DC and have a bunch of stuff that is already dc, stay that way otherwise your going to be spending some money for DCC decoders, and the controler of your choice, etc...
If you haven't started yet, DCC is my choice.
DCC sends out pulses that the decoders can read. Every decoder has a different address that is decoded through these pulses going through the track.
Some people like the old school DC stuff, and have very nice setups using this. I started later on when DCC was established, and I bought all DCC stuff with a bunch of decoders for everything. I don't regret it.
If you started the hobby with DC and have a bunch of stuff that is already dc, stay that way otherwise your going to be spending some money for DCC decoders, and the controler of your choice, etc...
If you haven't started yet, DCC is my choice.
jdetray
Well-Known Member
I'll take my shot at explaining the difference.
DC, which stands for Direct Current, is the traditional way -- and until fairly recently the ONLY way -- to control a model railroad. In its most basic form, DC consists of a power pack (sometimes known as a transformer) which has two wires coming from it that connect to your rails. Adjusting a knob or lever on the power pack increases or decreases the voltage on the rails, causing the motor in your locomotive to run faster or slower, thus changing the speed of the locomotive. If you have one power pack, you can control one locomotive at a time. If you add additional power packs, along with sufficient electrical switches and wiring, you can run more than one locomotive at a time. The wiring to do this quickly increases in complexity if you wish to simultaneously control multiple locomotives.
DCC, which stands for Digital Command Control, operates on a different principle. With a DCC system, full voltage is applied to the rails at all times. Unlike a DC power pack, the controller for a DCC system does not vary the track voltage at all. Instead, the DCC controller send digital commands through the rails. In other words, both track voltage and digital signals exist on the rails simultaneously.
Each locomotive is equipped with a Decoder that responds to the digital commands. The Big Deal about DCC is that the decoder in a given locomotive responds ONLY to commands intended for that specific locomotive. This is done by assigning a unique numerical address to each locomotive's decoder. For convenience, the address is usually the same as the road number that is painted on the side of the locomotive.
Even though a DCC-equipped locomotive is sitting on the track (which has full voltage on its rails at all times), the locomotive won't move until you send a digital command to the decoder in that locomotive, telling it to move. If you want locomotive #1550 to move, you press buttons on your DCC controller to send a command to locomotive #1550. The decoder in locomotive #1550 will receive the command and apply power to the motor in #1550. All other locomotives on the track will remain stationary, because you have not issued any commands to them.
It takes far longer to describe this process than it does to actually do it; the complexity is mostly hidden from view. DCC controllers are designed to make it quick and easy to send commands to one locomotive, then transfer control to another locomotive, or to a third loco, or to a fourth, etc. Once you have set a locomotive in motion, it will continue moving even when you transfer control to a different loco. The decoder in each locomotive remembers the last command it has received and simply continues to apply that command until you send a new command to the loco.
The advantages of DCC are readily apparent. You can control many locos with one DCC controller. Commands issued to one locomotive have no effect on any other locomotive. No complex wiring is needed to operate several locomotives at the same time. Many new locomotives are available with a DCC already installed. For the most part, DCC equipment from various manufacturers is compatible.
There are some disadvantages to DCC. A DCC controller is more expensive that a traditional DC power pack. Also, each locomotive must be equipped with a decoder, which is an extra expense. Older non-DCC locomotives can usually be converted to DCC by installing a decoder, but for some locos, this conversion is not simple.
For me, the advantages of DCC far outweigh the disadvantages. On the other hand, someone with an existing conventional DC layout and dozens of non-DCC locomotives may choose to continue using DC rather than spend the time and money to convert the equipment to DCC.
I hope this has helped your understanding a bit.
- Jeff
DC, which stands for Direct Current, is the traditional way -- and until fairly recently the ONLY way -- to control a model railroad. In its most basic form, DC consists of a power pack (sometimes known as a transformer) which has two wires coming from it that connect to your rails. Adjusting a knob or lever on the power pack increases or decreases the voltage on the rails, causing the motor in your locomotive to run faster or slower, thus changing the speed of the locomotive. If you have one power pack, you can control one locomotive at a time. If you add additional power packs, along with sufficient electrical switches and wiring, you can run more than one locomotive at a time. The wiring to do this quickly increases in complexity if you wish to simultaneously control multiple locomotives.
DCC, which stands for Digital Command Control, operates on a different principle. With a DCC system, full voltage is applied to the rails at all times. Unlike a DC power pack, the controller for a DCC system does not vary the track voltage at all. Instead, the DCC controller send digital commands through the rails. In other words, both track voltage and digital signals exist on the rails simultaneously.
Each locomotive is equipped with a Decoder that responds to the digital commands. The Big Deal about DCC is that the decoder in a given locomotive responds ONLY to commands intended for that specific locomotive. This is done by assigning a unique numerical address to each locomotive's decoder. For convenience, the address is usually the same as the road number that is painted on the side of the locomotive.
Even though a DCC-equipped locomotive is sitting on the track (which has full voltage on its rails at all times), the locomotive won't move until you send a digital command to the decoder in that locomotive, telling it to move. If you want locomotive #1550 to move, you press buttons on your DCC controller to send a command to locomotive #1550. The decoder in locomotive #1550 will receive the command and apply power to the motor in #1550. All other locomotives on the track will remain stationary, because you have not issued any commands to them.
It takes far longer to describe this process than it does to actually do it; the complexity is mostly hidden from view. DCC controllers are designed to make it quick and easy to send commands to one locomotive, then transfer control to another locomotive, or to a third loco, or to a fourth, etc. Once you have set a locomotive in motion, it will continue moving even when you transfer control to a different loco. The decoder in each locomotive remembers the last command it has received and simply continues to apply that command until you send a new command to the loco.
The advantages of DCC are readily apparent. You can control many locos with one DCC controller. Commands issued to one locomotive have no effect on any other locomotive. No complex wiring is needed to operate several locomotives at the same time. Many new locomotives are available with a DCC already installed. For the most part, DCC equipment from various manufacturers is compatible.
There are some disadvantages to DCC. A DCC controller is more expensive that a traditional DC power pack. Also, each locomotive must be equipped with a decoder, which is an extra expense. Older non-DCC locomotives can usually be converted to DCC by installing a decoder, but for some locos, this conversion is not simple.
For me, the advantages of DCC far outweigh the disadvantages. On the other hand, someone with an existing conventional DC layout and dozens of non-DCC locomotives may choose to continue using DC rather than spend the time and money to convert the equipment to DCC.
I hope this has helped your understanding a bit.
- Jeff
TrinityJayOne
N gauge fan
The above post is a really good explanation, and he's also right about it not be rocket science despite how complex it sounds. If you are science-inclined, it is technically a DC voltage that alternates like AC, only it is a(n asymmetrical) square wave instead of a sine wave. The frequency of the square wave is altered on the fly by the command unit in such a way that a binary signal is encoded into it. It's really quite clever if you ask me. 
I will also throw in a few features not mentioned above. Not only can you control loco speed & direction independently, you can also do things like turn headlights on & off, flash ditch lights, and play sounds if your loco is so equipped. It's also great for running multiple locos in a MU lashup. This is done by assigning each loco you want in the consist a 2nd address separate from the normal one. Then instead of sending commands to one individual train address you send them to the consist address, and all the trains you designated will respond.
I will also throw in a few features not mentioned above. Not only can you control loco speed & direction independently, you can also do things like turn headlights on & off, flash ditch lights, and play sounds if your loco is so equipped. It's also great for running multiple locos in a MU lashup. This is done by assigning each loco you want in the consist a 2nd address separate from the normal one. Then instead of sending commands to one individual train address you send them to the consist address, and all the trains you designated will respond.
Enola Yard Tim
Just call me Tim
Selector
Well-Known Member
Good advice and information so far.
Both systems of control require basically two wires, one to each rail.
In DC, you must dial up and dial down voltage. A loco with lights will begin to move as you dial up voltage and the light will get progressively brighter as the engine speeds up or hauls up a grade.
In DC, when one engine moves, they all move...and the same direction, no matter if you turn one of them around by picking it up and setting it back down the other way. The only way around this is to switch off the locomotive or block of the tracks and activate them by block control, say toggle switches or something more automatic. Automtic systems, ones mimicking DCC operations, exist.
With DCC, as stated already, you don't do any voltage changing. It's always full bore to the rails, usually around 15 volts, maybe 16. It just happens to be pulsed in such a way that the listening onboard decoder, always listening, hears instructions, or commands, directing it to 'do something'. You issue those commands through your hand-held paddle.
With DCC, you can have two locomotives facing each other on the same powered length of rails, both stationary, couplers not touching. You can make one or both locomotives move toward each other and lock couplers. This is impossible in DC. Well, not impossible...you would only be able to do this with with each engine on separately powered rails with a gap in the rails right under the couplers where they meet. No gaps needed in DCC because the decoder tells the motor which way to spin. In DC, the voltage polarity in the rails coming up to the motor tells it which way to spin. Unfortunately, as I already explained, when motors spin the same way, they make the locomotives with direct drives move the same way. When you pick up one of them and turn it to face the other way, you get the loco facing in reverse direction, but you have also changed the polarity the motor gets from each rail, and it will spin in the opposite direction to what it was doing before you turned the loco around. In effect, you entirely negated your swapping ends with the loco! So, you dial in voltage, and both locos begin to chase each other once again.
Both systems of control require basically two wires, one to each rail.
In DC, you must dial up and dial down voltage. A loco with lights will begin to move as you dial up voltage and the light will get progressively brighter as the engine speeds up or hauls up a grade.
In DC, when one engine moves, they all move...and the same direction, no matter if you turn one of them around by picking it up and setting it back down the other way. The only way around this is to switch off the locomotive or block of the tracks and activate them by block control, say toggle switches or something more automatic. Automtic systems, ones mimicking DCC operations, exist.
With DCC, as stated already, you don't do any voltage changing. It's always full bore to the rails, usually around 15 volts, maybe 16. It just happens to be pulsed in such a way that the listening onboard decoder, always listening, hears instructions, or commands, directing it to 'do something'. You issue those commands through your hand-held paddle.
With DCC, you can have two locomotives facing each other on the same powered length of rails, both stationary, couplers not touching. You can make one or both locomotives move toward each other and lock couplers. This is impossible in DC. Well, not impossible...you would only be able to do this with with each engine on separately powered rails with a gap in the rails right under the couplers where they meet. No gaps needed in DCC because the decoder tells the motor which way to spin. In DC, the voltage polarity in the rails coming up to the motor tells it which way to spin. Unfortunately, as I already explained, when motors spin the same way, they make the locomotives with direct drives move the same way. When you pick up one of them and turn it to face the other way, you get the loco facing in reverse direction, but you have also changed the polarity the motor gets from each rail, and it will spin in the opposite direction to what it was doing before you turned the loco around. In effect, you entirely negated your swapping ends with the loco! So, you dial in voltage, and both locos begin to chase each other once again.
amdaley
Member
Hello.
I suppose the easiest way to explain it is.
In DC you drive the track.The more you turn the control knob the more voltage you put on the track & the faster the loco will move.If you have two locos on the track then they will both move.
In DCC you drive the locomotive.There is always full voltage on the track.
Each locomotive has its own individual address number which you can change if you wish.You punch in the number of the locomotive you wish to operate & only that loco will move. You can have as many locomotives you wish on the same track but only the locomotive you select will move. All the others will stay exactly as they are until you decide to select one of them by dialing in its number on your controller. This is achieved by putting a small DCC decoder in each locomotive so a locomotive will only move when you select its address.If you want to read all about DCC then grab yourself a large coffee & read here.
http://www.dccconcepts.com/index_files/DCCadvice1.htm
Affiliate Disclosure: We may receive a commision from some of the links and ads shown on this website (Learn More Here)