DCC Layout Wiring

[ShinCanadaSen]

Hi,

I was wondering if there is a Benefit / Requirement of breaking larger DCC layouts into blocks and do they need to be insullated from each other ?

I have only set up temporary layouts with less than 30 Ft of track and I usualy run double loops connected by a Double Cross Over. I'm using Kato Unitrack and a Bachmann EzDCC controller. I usualy just split the out put from the controller to a feeder track on each loop.

I have been stock piling Track and I am startint to build bigger (Still temporary) Layouts and I just realized I need to figure out how to wire them properly.

Thank you in advance for your wiring wisdom.

[Bernard]

On large layouts I highly recommend breaking them into blocks. This way when an electrical problem arises you can figure out what area it has happened. The circuit breaker will light up to indicate which block has the short. Here is what they look like:
http://www.tonystrains.com/products/type_powerprotect.htm

[KenS]

As Bernard said, debugging shorts is really helped by being able to subdivide the layout. Even without circuit breakers (although I do recommend them), just being able to disconnect the feed to a block and see the problem go away will help speed up finding the actual cause.

The other reason is power.  A typical booster puts out 5 Amps (there are larger ones, and smaller ones like the Zephyr), and a typical N-scale train probably draws a bit less than a half amp (trains with passenger car lighting using bulbs probably draw well over 1 amp).  So, once you get more than about 8-10 trains running on a layout, you'll need a booster.  And having blocks lets you easily connect some to the original supply, and others to the booster.

It's a good idea to insulate both rails at a block boundry, although you can get away with a common rail and one insulated rail, but that makes diagnosing problems harder.  Also, you need to be careful about "phase" (i.e., the rail on either side of the insulator should be connected to the same source or to the matching output on a booster, unless you're wiring a reversing section). I've heard of people having problems with insulated Unijoiners shorting on curves, so putting the insulators between straight sections of track is a good idea, although I don't know how common a problem this really is.

It's also a good idea to feed track every six feet or so (2m) to avoid voltage drops in the rail.  DCC with multiple trains exacerbates this problem, but I've seen it happen on DC track with more than 20' from the feed visibly slowing a single train.  There's no problem with multiple feeds to the same block, as long as they come from the same power source and you keep the phase correct. And the bus wire to the feeds should be at least 14 gauge (about 64 mil diameter) for a reasonably large N-scale layout (larger with really long runs, or more than a 5 Amp supply).

There's a really good page of tips about details like that at: http://www.wiringfordcc.com/

I don't necessarily agree with everything he says, and some of his tips are more relevant if you're building a permanent layout you expect to keep for decades without changing it, but he has a lot of good info.

[Martijn Meerts]

Depends a bit on what you mean with "blocks".

If you just want to divide the layout into various sections, then there's no real requirements. For debugging you could insulate the tracks. If you add a booster, the parts the booster is providing power to have to be insulated.

If on the other hand you mean blocks for automated control (be it computer control or reed switches or whatever), there's a LOT of things to keep in mind =)