insulated rail joiners and power districts : LUSENET : Wiring for DCC : One Thread

I am presently building an N scale layout #N-18 from the Altas Nine N Scale railroads book. The problem for me is the book was written in 1994 for dc, not for dcc . I have a Digitrax Zepher on order and I'm planning on purchasing a MRC auto reverse loop controller for the one loop on the plan. My questions are 1) do I need to put in all the insulated plastic rail joiners to seperate the track into blocks when using dcc? 2)besides the reverse loop , where else are insulated rail joiners required on a dcc layout? 3) if I plan to operate 5-6 locomotives at a time do I need to seperate the track into power districts?

-- Tod Garthwaite (, March 20, 2003


I don't have the book so I can't comment directly on the track layout, but, you don't need to separate the layout into several electrical blocks. The beauty of DCC is that all the track is powered and you control individual engines. The only track section that needs to be isolated is the reverse loop. Insulate both rails at each end of the loop and feed the loop from the output of the MRC reverser.


-- Dale Gloer (, March 21, 2003.

Generally you don't NEED to divide the layout into control blocks just to run DCC operated trains. However, there are several good reasons for doing so. 1. You may want to disable power on staging sidings. [Saves power & eliminates phantom move operator errors.] 2. You may want to be able to disable power to certain track sections for trouble shooting. Use quick-disconnect, toggle switch or electronic CB to isolate one section from others. [aids troubleshooting & helps isolate operator errors from one another] 3. You may want to add block occupancy detection to operate signals at a later time. [requires separate blocks] 4. You may have power routing switches that cause problems at sidings. [track shorts occur when switch positions don't agree] 5. Reversing loop tracks always require a separate block.

Putting in insulated rail joiners as you lay rail is easier than trying to add them later.

-- Don Vollrath (, March 21, 2003.

Although it is not nessasary to divide your layout into power districts with DCC, you may want to consider it if you have contrasting operations running simultaneouly (i.e. yard switching w/ trains running the mainline in the background). You wouldn't want a short-surciut on the mains to innterupt your humping operations, would ya?

A downside (unless you want to do some additional wiring) is that you need one booster per power district. It is possible to create a seperate power district without another booster using a PowerShield device.

-- Maxwell R. Holmquist (, March 26, 2003.

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