I'm just starting to wire my new DCC layout and have some dumb questions. The trackwork is complete and divided into (8) power districts by insulating the track sections, feeders dropped from the track (not yet connected to anything), and the power bus run completely around the layout from underneath (14 AWG). I'm using an MRC Prodigy Advance and an MRC Booster plus two Tony's Train Exchange PSFour circuit breakers. With all that background here's my dumb questions: How do I hook everything up?? I understand that the feeders from the variious districts connect to the Rail Outputs on the PSFours. No problem there. My confusion is from the "Main Track" connection on the booster/command station to the PSFour and the interface with the power bus. Do I connect directly from the "Main Track" terminal to the PSFour DCC Inputs? or is the connection to the DCC inputs from the power bus? What connects to the "Main Track" terminal on the booster? I have all the books and instructions but none of them clearly explain that (at least not so I can understand it).
What I really need is for one of you guys who knows a lot more than I do (and thats most of you) to walk me through the whole hook up scenario and assume that I am an electrical/DCC idiot.
dadret wrote: I'm just starting to wire my new DCC layout and have some dumb questions. The trackwork is complete and divided into (8) power districts by insulating the track sections, feeders dropped from the track (not yet connected to anything), and the power bus run completely around the layout from underneath (14 AWG). I'm using an MRC Prodigy Advance and an MRC Booster plus two Tony's Train Exchange PSFour circuit breakers. With all that background here's my dumb questions: How do I hook everything up?? I understand that the feeders from the variious districts connect to the Rail Outputs on the PSFours. No problem there. My confusion is from the "Main Track" connection on the booster/command station to the PSFour and the interface with the power bus. Do I connect directly from the "Main Track" terminal to the PSFour DCC Inputs? or is the connection to the DCC inputs from the power bus? What connects to the "Main Track" terminal on the booster? I have all the books and instructions but none of them clearly explain that (at least not so I can understand it). What I really need is for one of you guys who knows a lot more than I do (and thats most of you) to walk me through the whole hook up scenario and assume that I am an electrical/DCC idiot.
I don't know what a PSFour looks like; however you said it was a 4 circuit circuit breaker. Id you ignore the booster (only needed if you run many engines at the same time), the following will work ( I have and use a Prodigy Advance):
Connect the Advance main track terminals to your DCC buss.
Connect the blocks (your feeders) to the output side of the circuit breakers (may be marked LOAD). Depending on the length of your track work; you may need to make short, heavy wire, busses for each of your blocks rather than run many long (small wire) feeders to the circuit breakers.
Connect the input side of the circuit breakers to the DCC buss which is hooked to the main track output on the PA.
Hook the program track output on the PA to a length of track so that you can use the features of the programming track (like reading CV's). This is the only way that you can find out what the existing CV values are, and is especially important to be able to read the loco number programmed into the engine.
dadret wrote:I'm just starting to wire my new DCC layout and have some dumb questions. The trackwork is complete and divided into (8) power districts by insulating the track sections, feeders dropped from the track (not yet connected to anything), and the power bus run completely around the layout from underneath (14 AWG). I'm using an MRC Prodigy Advance and an MRC Booster plus two Tony's Train Exchange PSFour circuit breakers. With all that background here's my dumb questions: How do I hook everything up?? I understand that the feeders from the variious districts connect to the Rail Outputs on the PSFours. No problem there. My confusion is from the "Main Track" connection on the booster/command station to the PSFour and the interface with the power bus. Do I connect directly from the "Main Track" terminal to the PSFour DCC Inputs? or is the connection to the DCC inputs from the power bus? What connects to the "Main Track" terminal on the booster? I have all the books and instructions but none of them clearly explain that (at least not so I can understand it). What I really need is for one of you guys who knows a lot more than I do (and thats most of you) to walk me through the whole hook up scenario and assume that I am an electrical/DCC idiot.
Engineer Jeff NS Nut Visit my layout at: http://www.thebinks.com/trains/
dadret wrote:Thanks for the help - a bus per district makes a lot more sense than one for the whole layout.
It also becomes important when you start looking at the scalability issues and the weakest link, the output of a single booster. If you don't plan ahead you can easily be faced with a situation where your mainline is all on a single district powered by a single booster. Then you find that you are running more than one train at a time on the mainline with consists built up of sound locomotives. At that rate you can find that you have exceeded the 5A limit of many boosters and you need to add capacity. With everything being a single block you are now pulling out the razor saw or dremel tool, cutting gaps, wiring a new breaker and more. Not my idea of a fun Saturday afternoon. Now if they ever make boosters that can be wired in parallel and load share, then we can add boosters until the wires glow or the heat sinks on the breakers become heaters.
Since you have multiple boosters AND the breakers, you have both power districs and sub-districts. Think of it as branches on a tree. The sub-districts are the leaves - the actual track sections that get power. Depending on how much track each breaker output will power, this may contain more than one set of feeders. Those all tie together and go to one output of the breaker. Ditto for the next group of track sections. These track sections should have gaps in both rails seperating them from one another.
Up one level, to the individual branches of the tree - The PS-Four actually is two PS-Twos on one board - notice int he instructiosn it shows you how to connect the inputs together to power all 4 output from one input. Out of the package they are actually not connected. If you group the breakers and boosters at a central point, there really is no bus here, the booster outputs connect to the breaker inputs. If you distribute the breakers under the layout but put the boosters at a central point, you will have a bus line that runs from each booster output to the breaker inputs. If you layout is rather large, it is probably best to distribute both the boosters and the breakers. For example, the long wall in my basement is 53' long. If I put two boosters at one end and divided the length in half, the wires from one booster would run over 25' before they even got to the track they were going to power. The better way would be to locate the second booster down nesr the opposite end to keep the overall length of the track power wires as short as possible.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.