Trains4Africa
Because all Boys (and some girls) love Trains

DIGITAL COMMAND CONTROL

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Apart from visiting individual DCC manufacturers for support, manuals and FAQ’s, there really are many good resources on the topic of Using DCC! I do not want to duplicate things here – what I do want to share, are some obscure but useful bits and pieces I have found.

Simplicity:  Getting started with DCC should be a no-brainer and you do not need to get technical to run a train! in fact, running train “out of the box” usually entails nothing more than attaching (2) wires to the track (just like you would a traditional DC), and ensuring that you have a DCC fitted train on the track.

Building an Empire ?
The fun really starts when you start adding turnout points, loops, blocks, light signals..this is when you should stop for a second and become mindfull of the DCC selection choices you make..here’s why

Then, when you’re ready, you can expand by adding accessory decoders to activate your turnouts and turn building lights on and off. As you grow, add more decoder equipped locos to your fleet. And if you feel like expanding your empire further, DCC also allows you to take advantage of advanced capabilities!

Here’s an interesting article on the history of Command Control..

Made up your mind, and just want to get going?

The following Articles may help you get started:-

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If you are interested in the “Bits and Bytes” and other Technical details related to DCC, then these Articles will get you started:

Note: Most of the material presented here, has previously been exclusively available to a few engineers and system developers working on DCC projects. Needless to say I invested a lot of time and effort into sourcing, translating, and even reverse engineering various DCC systems/components- not to mention translating various Manuals and reference work (mainly in German).


If You’re still reading..you probably need

a quick introduction to DCC..

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DCC stands for “Digital Command Control”

The NMRA trademarked the term DCC, so while the term Digital Command Control is sometimes used to describe any digital model railway control system, strictly speaking it refers to NMRA DCC standard for a system to operate model railways digitally.

Essentially a DCC system consists of:

  • DCC Protocol
  • Control Hardware
  • Control Software

DCC Systems typically consists of some of the following feutures:

  • Accessories
  • Auto Reversing
  • Command Stations & Boosters
  • Computer Control
  • Detection & Signaling
  • Function Decoders
  • Mobile Decoders
  • Power Management
  • Power Supplies
  • Sound Decoders & Speakers
  • Stationary Decoders
  • Throttles
  • Transponding
  • Universal Panel, IR & Radio Receivers

In short, DCC is a system where digital commands are sent to the locomotives through the rails.

With traditional DC, you would typically use a 12V transformer, and by adjusting the power that is sent to track, the train would either go faster, slower or stop. By reversing the polarity, the train could be made to move in the opposite direction.

Have a look at this test layout for an example of DCC wiring options. (this is dated, but should get the point across)


Here’s a quick , non-technical, discussion on the issue of DCC vs DC..

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One of the biggest drawbacks of a DC system is that it requires separate power packs for each section of track (referred to as a Block)  and probably a complex control panel to keep each locomotive electrically separate from each other.

Another key drawback of a DC system is that only a single train can be controlled at a time on a single block (well you could just put two trains on the same piece of track- they will however behave very similar- stopping a train stops all trains).

dcc_5Enter DCC..

  • DCC allows independent control of multiple locomotives within the same block.
  • DCC allows you to digitally control turnouts and signaling as well and includes features such as multitude of sounds, block detection, momentum control, and the ability to lash together locomotives.
  • DCC is standardized, which means that locomotives equipped with decoders from various manufacturers may be used with any DCC system.
  • Although DCC has many advantages, one of the minor drawbacks is that when it comes to computer control, there are differences in competing vendors products, which may result in DCC control equipment becoming incompatible – Please read more about this issue, before making your final choice of a DCC system.dcc_2

So in short, what do you need to buy to get started?

Please read the “Which DCC System to Purchase” Article before making your purchase decision.

All DCC systems consists of five basic components:

Command Station

  • The heart or brains of DCC. The Command Station is a dedicated computer that communicates with all other parts of the DCC system
  • Selecting the brand and model of Command Station is key to selecting the type of Throttle controls as well as feature expandability of the system.

Throttle

  • Also called a Cab, is the man-machine interface between You, the engineer, and the Command Station controlling the train
  • Various Throttle equipment styles exist
  • Some systems use a plug-in, walk-around Throttle, with the possibility that more than one can be used at the same time
  • Some systems have Throttles built into the Command Station
  • Each brand of DCC system requires their own brand of Throttle or Engineer’s Cab, and their specific type of Throttle to Command Station wiring interface
  • It is typically not possible to intermix brands due to manufacturers proprietary implementation of the Control and/or Feedback busses.

Booster

  • A power amplifier of the communication signals from the Command Station into power applied to the track
  • Some starter systems combine a Command Station and Booster into one box
  • Almost all Boosters require an external Power Supply
  • The ampere rating of the Booster and Power Supply will limit how many locos you can run at the same time
  • Some Boosters are in a separately available box and may be controllable from a Command Stations of a different brand.

Power Supply

  • An AC transformer or DC power source for the Command Station and track power Booster
  • Depending on the system you buy, the Power Supply may or may not be included – check with your dealer
  • An additional Power Supply is usually required with each additional Booster

Loco Decoder

  • An electronic receiver inside the loco out on the track
  • The Decoder receives communications from the Command Station and controls the loco motor and lighting effects
  • Some Decoders also add locomotive sounds to operation
  • Every DCC controlled locomotive must have its own decoder
  • Any brand of Loco decoder should work with any brand of DCC Command Station / Throttle equipment.

dcc_1You can easily start setting up a DCC system, by buying a systems that includes the above basic items, plus a few additional Loco Decoders.

dcc_3However, as your model railroad grows you may want more DCC equipment, including:

  • additional Throttles for multiple users (get the same brand)
  • remote Plug-In panels for walk-around Throttles
  • Accessory Decoders for DCC operation of track switches (turnouts)
  • Auto-Reversing track controllers
  • more Power Supplies & Boosters
  • Electronic Circuit Breakers for separation of track circuits into multiple power districts
  • or even Radio equipped Throttles

References: NMRA, DCCWiki, Lenz, Digitrax and others

If you are interested in the “Bits and Bytes” and other Technical details, then these Articles will get you started:


Page Credit: Stéfan Stoltz