The latest post indicated how the Branchline Automation was failing due to an issue with the track sensors becoming flaky.

As a follow up, I changed some of the sensors, added a couple new ones, and even found the B830 block that I was missing before, albeit not how I expected it.

On the plus side, the automation now benefits from having a physical sensor for B830, which is the canyon bridge on the branchline.

First I changed the “flaky” NCE BD20 sensor from block B821. I replaced it by a BD20 fitted with an adjustable potentiometer, hoping I could somewhat adjust the sensitivity better. And at the same time I found on the terminal block an orange wire directly feeding the B830 canyon block:

Well, that didn’t quite work as expected.

First it turns out the BD20 fitted with the adjustable potentiometer seemed to have… less sensitivity? I had to double the loop in the coil to be able to detect the Amtrak engine properly.

And that orange wire, connected to position 1 on the terminal block, didn’t do anything either. It just never triggers. I double checked the wire and, then also had Orion check it for me, and it does indeed go to the canyon track but somehow that doesn’t register as being used. That’s… puzzling.

Fine, moving on. On the other side of canyon, the track reaches Smith Flat, where I had a sensor for B850, a section going into a little tunnel. I traced the block before and added a sensor to what I expected to be “the Smith Flat” block on the old panel, which I’m now labeling B840:

That’s all good except… that B840 sensor triggers when the train enters the canyon block, all the way up to Smith Flat. It’s as if the entire section of the branchline after Angel Camp were power just by that panel.

Fine, maybe it’s just one big block after all, and that sensor that I mistakenly labelled B840 covers what I describe as both B830 and B840 on my automation map. I can deal with that, especially since it’s the one block I needed for the automation script.

I have also updated the mapping of the blocks on the NCE AUI01:

New sensor map for AIU01 address 48 for the Branchline sensors:

Bit	JMRI	Description	Bit	JMRI	Description
1	752	B801 Yard Track 1	8	759	B850 “Tunnel”
2	753	B802 Yard Track 2 (unverified)	9	760	B860 “You Bet”
3	754	B803 Yard Track 3	10	761	B870 after You Bet
4	755	B821 “Station”	11	762	B880 polarity reverser
5	756	B823	12	763	B890 Rodgers Junction
6	757	B830 “Canyon”	13	764	--
7	758	B840 “Smith Flat” B830 “Canyon + Smith Flat”	14	765	--

Entries in bold are actually wired with a sensor. Others are reserved for future deployment.

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