Pairing a BDL168 with a PM42

[VonRyan]

So the club I belong to is looking to implement detection into our operations. I'm the one working on getting the hardware end of things put together.

The diagram that Digitrax has on their website for the BDL168 shows that the board has 4 points for power input, but in their illustration it shows all four points as being commoned together as one power-input feed.

Since the club uses PM42s for short-circuit protection, which has four protection zones, my thought process has lead me to wonder if the positive/front-rail/colored leg of each PM42 could therefore correspond each to one of the four input points on the BDL168, thus 4 groups of 4 of the 16 detection zones could thus be protected by the PM42.

Has anyone done this? Or at least is it possible to do? I just want to make sure that there isn't a requirement that the four power-input feeds of the BDL168 be commoned together as one. Google didn't show me anything remotely useful.

Thanks all!

[jagged ben]

I can't imagine that connecting the different BDL168 zones to different PM42 sections would create a problem.  See figure 5 of the instruction manual for corroboration; it involves a reversing section, but reversing needn't be involved.   I'm less sure you can put the different zones on different boosters, although the manual language implies such.  But you might want to check with Digitrax, .

[bdennis]

Cody,
It all depends on the layout set up and the power districts..
If you have multiple BDL's then the outputs of the PM42 can be spread across multiple BDL's
The key is to remember that the BDL needs to be connected to the power district in groups of 4.
Being a club I would imagine that you have a large layout and probably more than 1 power district..
The key is to work from both ends..
Look at how many power districts you have.
Then look at how many blocks you need to create within each power district.
Then spread hose blocks across the 16 ports on a BDL (remembering that you need to group them in sets of 4)

Make sense??

You may end up with 1 or 2 blocks not used on a BDL if you have multiple power districts on 1 BDL.

If you want to share a layout diagram or a power district diagram, I'm sure there will be many here to help. I personally have designed this type of thing on about 5 layouts both large and small, so more than happy to help.

Brendan.

[VonRyan]

Cody,
It all depends on the layout set up and the power districts..
If you have multiple BDL's then the outputs of the PM42 can be spread across multiple BDL's
The key is to remember that the BDL needs to be connected to the power district in groups of 4.
Being a club I would imagine that you have a large layout and probably more than 1 power district..
The key is to work from both ends..
Look at how many power districts you have.
Then look at how many blocks you need to create within each power district.
Then spread hose blocks across the 16 ports on a BDL (remembering that you need to group them in sets of 4)

Make sense??

You may end up with 1 or 2 blocks not used on a BDL if you have multiple power districts on 1 BDL.

If you want to share a layout diagram or a power district diagram, I'm sure there will be many here to help. I personally have designed this type of thing on about 5 layouts both large and small, so more than happy to help.

Brendan.

At the moment, we don't intend for the entire layout to be under detection. We're an N-Trak club, that uses loop ends, and dispatching through JMRI, so we plan to implement the detection on the side of the layout opposite the dispatcher.
Since our modules don't always end up in the same configuration, I'm working on making the detection system splice into various points as needed. That part I already have figured out.

We use a lot of PM42s on the layout. But I'm only concerned with one that will be used to run the far side of the layout. Since each of the four sections of the one PM42 control one each of the Red/Yellow/Blue/Option-Blue, the BDL168 will divide further a segment of each of those tracks into 4 sections. I'm looking to spread the 4 sections of the PM42 across the 1 BDL168.

[bdennis]

Cody,
OK sounds like a plan..
You can have each of the 4 PM42 sections on each of the groups of 4 ports on the BDL168. So this will give you 4 detection sections for each track (Red / Yellow / Blue/ Option-Blue).
Per your comment above:
Since the club uses PM42s for short-circuit protection, which has four protection zones, my thought process has lead me to wonder if the positive/front-rail/colored leg of each PM42 could therefore correspond each to one of the four input points on the BDL168, thus 4 groups of 4 of the 16 detection zones could thus be protected by the PM42.

Yes your thoughts process is correct..

[mmyers]

I sat down With A.J. several years ago and discussed detection on NTRAK modules. He suggested we build small "detection modules" p. 1 footers would do the trick with all of the required electronics mounted to it or able to connect easily to it. Each module would have a gap in the center for each track so that each side was feeding the modules on its side. This would give us flexibility in set up so that we could just place a detection module wherever needed.
 We have yet to implement it but that's because our present detection using BD22's for each power district is working.

Martin Myers