Star Wiring

To do correct DCS star wiring you will need one common and one hot per track block. You are proposing a hybrid system of star wiring for hot and buss for common.

Don, many of us with larger layouts have found it more practical to use Buss Wiring which uses the larger size common buss.  Our DCS engines are running great.

Thanks for the speedy replies.  I have wired several large layouts, conventional, TMCC and Legacy, but do not have any experience with DCS.  Susan, your experience is very interesting as a buss system is what I am most comfortable with.  However, the owner is very insistant that all the power leads be star, 2 wire and the same length.

Hey Don... Barry's wiring suggestions work really well. They may be in the archives someplace but  this is sort of how it goes..... From the tiu output channel, paired wires to a terminal block. A lighted bulb connected to the terminal block....Paired wires out to each block .

My experience has led me to believe  30 feet is about the right length, Too many short blocks don't work as well. Perhaps 4 or 5 blocks per tiu channel although . Only the center rail needs to be insulated.  A set of paired wires  (hot & common)  should be the same length but  different sets certainly can be different lengths. Even the terminal block can be located at a handy spot  close the blocks, We have some runs of over 30 feet from the tiu output to the terminal block..  Hope this helps.

Test as you go ...

We're running 4 tiu in super mode with a great dcs signal. All  transformer are phased with heavy wire joining the  U connections on each post war ZW   (of them)

 other will chime in I hope.

My large layout is wired with hots going from a toggle-switched control panel via 14-gauge wire, one feed per block, and common going from U posts through a 12-gauge buss loop with periodic drops not block-related.  Runs fine, both conventional and DCS. 

It's his layout, so he can wire it any way he wants, necessary or not. 

I strongly recommend not using any wire thinner than 14-gauge stranded.

Bulbs supposedly not required with Rev L TIUs.  There is no requirement that wires be the same length; this was a theory that was withdrawn years ago.

Don, The runs to different blocks do NOT need to be all the same length.

also, Have him Get Barry's DCS Companion Book V2, available from MTH, It's the last word in DCS.

Thanks to all for taking the time to share your expeirence.  As RJR says it is his layout, but at least we have your combined expertise to help him make wiring decisions.