As work on the control panel continued, I realized that my power distribution wiring was not as clean as I would have hoped. Some occupancy zones would detect properly and some just would not. And if I did the quarter test in some places more than one PM42 feed would trip. I had already decided that there should be a 1:1 relationship between PM42s and BDL168 zones -- bought a second PM42 and installed it, This exposed a number of issues that had probably been there all along. Some of my track wiring was a mess. So I made up a little diagnostic tool with a 10kohm resistor and a set of test leads I could clip to the track. And just went around the layout, clipping the resistor across the track and seeing on Loconet Checker which detector zone lit up -- making a map of how the occupancy zones saw things.  I was appalled to find that in some places multiple zones lit up -- expletive... And in a couple of spots nothing at all... guess that was why my test trains always stalled there...

Common problem was not keeping the track 'b' side separated -- that was why I got multiple trips. When the PM42 is connected up, there are separate track A and track B leads for each zone. No commonality. Where I followed the common 'B' strategy documented in the BDL168 docs I got into trouble -- nice diagram but not when the power feed is managed. Now I am going back through the layout and reconnecting all the track power drops to the BDL168 zones -- but being careful to not cross-connect the 'B' leads. All that really means is that within a BDL group of four sensors I am allowing for a contiguous 'B' rail and breaking the 'A' as needed. In between these groups the track is gapped on both sides.

In the yard and engine service area I had a different problem -- with a bunch of sound engines sitting on adjacent tracks I was pretty close to the PM42 trip settings. New strategy breaks up the heavily loaded tracks between two power management zones to spread the load.

This round is not too bad. Just a matter of removing the old cross-connects and putting in different ones, hopefully better. And dreaming of a status panel for the yard... no end of fun.