Quick question for someone. After running a few test runs, I decided to power the frogs of my Atlas N-scale code 55 turnouts. Easy enough, since I am using Tortoises. However (defined as a word that means disregard everything before this word), everything is also wired through Digitrax BDL-16x block occupancy detectors.
The easy solution is to just tap into the feed from the BDL-16x to the corresponding section. But, there, below or adjacent to most of my Tortoises sits a perfectly good Digitrax power bus. What is the punishment I will see from just tapping into that, as opposed to the feed from the BDL-16x for the frog? My main concern is what sort of weird behavior I would induce when the locomotive bridges the gap between the frog and the block.
- Mark
Wierd is probably the word for it. There's something else to consider - the main but vs the output from a section of a BDL-168 - the BDL-168 section is going to be at 2 diode drops, 1.4V lower voltage than the track bus feeding the input of the BDL-168.
If the area around the turnout is detected, you should also have feeds from the BDL-168 nearyby. For best results, you would make the turnout plus a little bit of track in each direction a seperate detection zone, so that you can interlock the turnout controls and not be able to throw a switch under a moving train. That part often gets skipped because it saves a lot of money in having fewer detection sections, and you can mostly simulate the same thing by using logic in a panel to not allow the switch motor to operate if the block before or after the turnout is occupied.
I would just bite the bullet and tap off the BDL-168 section that the turnout is part of. We know that will work.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks Randy (which I seriously thought about adding to my original post in anticipation). The plan all along was to just tap into the BDL-16x feeder for the block in question. But, I was wiring up an edge connector for a Tortoise and practically had to move the bus wires to put it in place!
I had not thought about the voltage drop, but it is noticeable. I have one section that is temporarily wired directly through the bus (I need to order another BDL-168, although I will probably defer that to the fall since railroad construction season is about to be pre-empted by lawn season), and the locomotive performance is noticeably different. Enough that I have considered opening up the command station and boosters and turning up the potentiometer. It's probably not an issue since I program the speed tables and such based on speeds in detected sections, but like I said, it is noticeable.
The other reason to not worry about it is that pretty much everything except possibly a few spurs will go through a BDL, so everything gets dumbed down the same.
Tonight will mark the actual wiring of one or two of 23 Tortoises that are in place to an SE8C. I keep waiting for the Jack Wabbit Quad to be released to avoid having yet another device to get feedback to the Loconet. The web site says "due in August 2013" and last spring DCC Specialties/Tony's told me they were going into production. At some point, I will move on to something else and then the crazy things will show up! Or, they'll come out and be noticeably more expensive than the current options.
Well, you could just use DS64's since they already feed back to Loconet. And yes, even if you don't hook up contacts tot he inputs of the DS64, it still reports to Loconet if you use local control pushbuttons. Is the Jack Wabbit Quad going to actually have Loconet, or are they just saying "feedback'? Because all other DCC Specialties stuff that says "supports feedback" just means they have contacts that you cna connect to an input device for your DCC system, none of them (so far) support direct connection to Loconet or Expressnet or NCE cab bus.
The Jack Wabbit Quad is supposed to be offered in a couple of versions, one offering feedback direct to the Loconet (as well as versions for NCE and Lenz). Or so they say.
Streamlined Backshop has it listed for something like $84 retail and they were offering it for around $76. Of course, they had none available. Walthers actually lists it as a future product with no dates. According to Streamlined Backshop, there is one feedback version with different plug-in modules to support the DCC systems. Each unit includes a module and has a specific part number by that module.
Hmm, Tony's doesn't even list them, must not be ready yet. Possibly waiting approval from the vendors for the interfaces, at least with Digitrax you must submit commercial products for certification that they actually work per Loconet specifications.
The DS64 runs 4 Tortoises, can handle local pushbuttons and/or feedback, is is available for $50 or less.
Tony's had them listed before they redid their web site. They are still there somehwere, only buried.
I am going to reassess this in the fall. Right now I am about to dial down the major construction work until then, and things pretty much got a little farther than I expected. The SE8C handles the "front end" turnouts of the lower level staging/storage area pretty well, and I am going to have to install another SE8C near the "back end" for signalling purposes, anyway. Unfortunately, while one might have handled all the signalling needs, the distance is just too far for the acceptable signal cable length. It's not a bad deal, either, since for about $100 it controls up to 32 signal heads and 8 tortoises, including feedback. At that price, it is almost worth installing them just for tortoise control and using the signal heads to drive LEDs on the fascia (which would only be handy for the lower level staging tracks).
Then I have one double-track grade crossing (possibly two) on the horizon. For that I am leaning heavily toward Logic Rail Grade Crossing Pro IRs. The trackwork for both is down, but no ballast or scenery so installing that would be pretty easy. No gates, just flashers, at least that is the current plan. The Logic Rail route gives me a lot more control over when to start and stop the flashers than just using block detection. That is on next fall/winter's plan, unless I get ambitious for that type of project between now and then.....something that has been known to happen.
Looks like the Jack Wabbit Quad is now on the market. Tony's has them for $65 with the LocoNet connectors on the board.