Question with long description of our club setup:
Referring to Allan Gartner's Wiring for DCC, Track Part 1 "Train does not operate properly when crossing between booster districts", our club Digitrax Duplex setup failed Step 5.
Our setup: Three distributed booster areas, A, B and C (large layout). Digitrax Duplex HO with common rail wiring. PSX short circuit boards on each block - some PSX feed 2 blocks.
For A and C, the "black" drops for each block tie into a separate "common" that ties into a "Common" ground bar.
For B, we have not (yet) cut the RR common "black" into separate sections as we did for A and C. All blocks in that area tie into a single "common" bus. The end of that common run ties into the ground bar mentioned above.
Black feed from all the PSXs in all 3 areas tie into the same ground bar.
C transfers to A in one place, and to B in 2 places.
At each of these 3 transfers, the voltage across the gap of the red rail (Step 5 in Gartner's writeup) reads ~28 VAC- double the voltage across red and black within each block. So we get shorts, restarts and hesitation crossing between the booster boundaries.
1. Can we make this work without cutting the black common bus in area B into sections for each block as we did for A and C ?
2. What is going on that gives us double voltage in Step 5 of Gartner's wrietup ?
Walt in Sausalito