Having some trouble figuring out the wiring for block detection. Here’s the background:
A. HO scale layout, 17’ x 13’.
B. Two loops / ovals, one on the outside (the main) and one on the inside (the branch line) which does not always parallel the main.
C. I have one Digitrax booster, which I will route to a PM42. The four outputs from the PM42 will be:
(1) the main;
(2) the branch line;
(3) the engine servicing area (roundhouse, turntable, etc.); and
(4) the yard (which is 10 feet long and like a peninsula outside of the 17 x 13 footprint).
D. I want to include block detection on the main and the branch line through two BDL168 boards from Digitrax.
E. It occurred to me that there would have to be an incredible amount of wiring if I put the BDL168s in one central location because, as I see it, I would have to run heavy gauge wire from the vicinity of the BDL168 all the way to each block (each a “home run” if you will). I want to avoid or minimize this if possible.
F. My thought was to put one BDL168 at one end of the ovals (call it the left side) and one at the other end of the ovals (the right side). I would then:
--Route the PM42’s power sub-district 1 (the main) to a tee / a split, with one side going to two zones of the left BDL168 (giving me eight detection blocks) and the other side going to two zones of the right BDL168 (giving me another eight detection blocks).
--I would do the same thing with the PM42’s power sub-district 2 (the branch line).
This would mean that the left BDL168 would handle eight detection blocks of the main on the “left” side of the layout and eight detection blocks of the branch line on the “left” side. The right BDL168 would do the same at the other end. At the end of the day, I would have:
--Sixteen detection blocks on the main (eight handled through the left BDL168 and eight handled through the right BDL168); and
--Sixteen detection blocks on the branch line (eight handled through the left BDL168 and eight handled through the right BDL168).
G. The runs from the left and right BDL168s would be shorter, overall and on average, saving a considerable amount of wire (and cost).
1. Does anyone see a problem with this? Are there any particular consequences to having each BDL168 handle part of the main and part of the branch line?
2. When I eventually get train control software, will I still be able to “hook” together, logically, half of the main line blocks from one BDL168 and the other half of the main line blocks from the other BDL168?
3. Does everyone just bite the bullet and run rather long heavy gauge wire from their BDLs at a central location and out to detection block? And doesn’t take an fairly significant amount of wiring?
Any thoughts would be most appreciated. I’m new to this, and I did not see anyone asking this particular type of question before. Go easy on me.