Block Detection and Signals


D&J RailRoad

D&J RailRoad

Professor of HO
I tried for a month to get a Digitrax BDL168 block detection board to work on my layout. One of the mistakes I made in the setup was in connecting a ground wire from to the command station to the BDL168. All wire connections are supposed to be connected to each pair of connectors on the BDL168 except the ground wire. I missed that little note and may have damaged two BDL168s. I sent them off to Digitrax for check up and repair as they still didn't work right after I discovered the mistake with the ground wire.
I am looking at the Atlas and the International Signal System detectors and signal systems which both seem to be easier systems to setup. I saw one demo of the atlas system. Right out of the wrapper, a few wire connections and it was operating a three color signal flawlessly in a matter of minutes. No assignment of address. No board configuration. No loconet configuration. Just a signal control and block detection. I will have an opportunity to see the ISS system next week, then I will make a decision.
As for the BDL168, ISS material can use it for a block detector. I'm a bit leary of this but will take it with me to the demo next week.
One way or another, the layout will have a signal system.
 
You might want to try Azatrax signaling stuff. They operate by infrared detectors which are completely separate from the track power. They have an ad in the latest edition of MR. Depending on what kind of layout structural support you have (a 2x4 directly under where you want to put a detector makes it more difficult to use the under-track reflective method, but you can also mount the IR transmitter and the receptor above ground so the train simply breaks the beam as it passes. The connection to the module is a little different, but the diagrams are quite clear. IR can also be used to activate crossing lights, gates, and even a crossing bell.
 
And the Azatrax 8 channel unit can connect directly to a RR-CirKits TC-64 with a standard RR-CirKits ribbon cable.
 
I don't think I want to go with IR. I have way to much layout for that. Over 6 scale miles of double track mainline.
 
My opinion with signals is you either go with just block detection or full block and interlocking control. It seams once you go above block control you might as well just go all the way. I also hear many people say to keep signal systems isolated from track power to reduce any interference and complications. Keep the track and signals operation off their own systems just for trouble shooting reasons. Yes you will have to have some communications between signals and track but I feel that the K.I.S.S Rule is best..
 
I saw a demo of the ISS block detection system and it looked pretty easy to install. I can use my BDL168 boards with it for detection but I have to change the detection action from pulling up the voltage to pulling it down to work with the ISS boards.
I will be going to the Timonium show this weekend with the primary objective to find ISS equipment. If I can't find any then I'll order some of it on line.
 
http:// https://sites.google.com/si.../construction/block-detection-and-signaling-1
D&J RailRoad said:
I saw a demo of the ISS block detection system and it looked pretty easy to install. I can use my BDL168 boards with it for detection but I have to change the detection action from pulling up the voltage to pulling it down to work with the ISS boards.
I will be going to the Timonium show this weekend with the primary objective to find ISS equipment. If I can't find any then I'll order some of it on line.
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I would look into the rrcirkits block detection...it is fully loco net compatible and is completely isolated from track power. It also doesn't have the problem of voltage drop from block to block. It uses current transformers which your feeders pass thru. You only need a 12 volt power supply and a loco net connection. You do not need to connect a ground to it.

My website has some info about it.
 
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This is so fricken aggravating. I am trying to hook up another BDL168 to my system for block detection. I had a problem with one track that showed constant occupancy. I was beginning to think it had to be the board. As a last effort to prove things out, I cut the leads from the track buss the whole 70 foot length of track, one lead at a time and rechecking the LED on the test plug. Finally, at the very extreme end, I found one lead was connected to two tracks. At the very last possible one I could cut loose. Why couldn't I have started at that end and find it right away? Yeah, throwing tools for a few minutes.
Ok, now the next problem to over come. When I plug the loconet into the BDL168, the whole system locks up and I can't control any trains even if I plug directly into the loco net with the DT100R or the DT400R. But the occupancy detection works when I tip the loco off the track. When I unplug loconet from the BDL168, I can control trains but the block detection doesn't work on the board. LED stays lit even when loco is off the track.
It can't possibly be this hard. Is it because I'm using code 83 track? Is it because the length of block is too long? Is there a secret spit solution I have to put on it?
 
Ken,
Reading your thread, my first thought is do you have a bad loconet cable? One of my most useful tools is a cable pair scanner to test loconet or other data cables.

Also, a 70 ft block sounds like a really long block. As for starting on the 'other end', my dad taught me to start in the middle.

Block control is all about careful, well organized wiring, regardless of who makes the sensors and hardware.

Good luck,

Joe
 
I have tried several loconet cables that work on other parts of the layout.
I don't know that 70 feet is too long. The manual doesn't specify size of block limitations, but ghen how would that effect loconet?
 
Is the PM42 essential to the setup?
How is the SEC8 and the BDL168 linked together or are they linked besides the power supply?
 
Ok, this is jumping way ahead of where I am now, but how does the ribbon cable determine which track side lights operate?
Does you system use the three aspect light, i.e. green, yellow, red?
You mentioned an interlock. What is that?
 
I think what I am going to have to do here is set up an isolated layout with a single command station and just one piece of track about 2' long and build up from there. There is obviously something in this that is being taken for granted that needs attention. Perhaps the BDL168 is intended for a small layout on a 4x8 sheet of plywood.
 
This is so &%@$%%@ aggravating.
I don't know how many times I checked the wiring to the 44 pin strip and confirmed each wire was on its proper pin.
Tonight, after setting up the simplest Digitrax setup possible and it still didn't work, I noticed that the ground wire from the command station was soldered to pin M instead of pin 11. I fixed that and everything is working properly now.
I often wonder how many things I'm really screwing up in my daily life because what I think I see isn't really what is.
Well, it's on to trying to set up the signals now. I wonder how many things I'll screw up with that.
 
Thanks Jerry. I want to setup a three aspect signal system with two aspect going into the main yard and staging. I still a little unclear how an approach to a turnout is signaled, from the points end or tge frog end.
You can take a look at the size of this layout in the thread I started in the layout construct and design section titled" D&J Railroad from scratch".
 
Ken,
A less technical question-what kind of signals are you using; searchlight, G, D? Also wondering which brand or brands you're using?

Thanks,
Carl
 
D&J RailRoad said:
Thanks Jerry. I want to setup a three aspect signal system with two aspect going into the main yard and staging. I still a little unclear how an approach to a turnout is signaled, from the points end or tge frog end.
You can take a look at the size of this layout in the thread I started in the layout construct and design section titled" D&J Railroad from scratch".
Click to expand...

On a real railroad, the signals on an approach would be located sufficiently before the turnout to enable the train to be stopped before overrunning the signal and the turnout. With heavy freight trains and depending on the speed of the train, this could be a mile or more from the turnout. However, that's pretty impracticable on a model railroad. If you use a lot of momentum in your engines, either from flywheels or from electronic controls, you would need to allow for this in setting the distance from the turnout. If approaching the point end of the turnout, you'd want to indicate the route the train is to take, and thus the speed at which the train should approach the turnout. OTOH, if approaching the turnout from the frog end, you need to indicate to the engineer if the turnout is thrown against the oncoming train, so as to avoid a derailment, or if the points are set for the oncoming train.

Prototype and model railroad signal systems vary according to the railroad, the era, and other criteria. One source of data is NMRA Data Sheet D9e.1, dated May 1950! Another was used by the Santa Fe R.R., date 1995 (before the merger), which can be found at www.ludsten.dk/us_signaling aspects_atsf1995. There may be others.

Personally, I use signals only for purposes of indicating turnout positions, where I can't see the turnout directly, and for indicating polarity (under DC) agreement or conflicts between blocks. One note, most signals have the red light as the lowest on the pole, which is the exact opposite of automobile traffic signals. I don't know why that is, except maybe to insure the light is closest to the engine cab. Some of the model signals I've encountered have the red on top, which is not correct for most though not all applications.
 
I i tend to use the three aspect for block signaling. I have a few BLMA signals on order. I guess I need to study up on how signals are used on the BNSF and the UP.
 
D&J RailRoad said:
I i tend to use the three aspect for block signaling. I have a few BLMA signals on order. I guess I need to study up on how signals are used on the BNSF and the UP.
Click to expand...

I'm finding your use of the term "aspect" confusing. If you look at this page,

http://broadway.pennsyrr.com/Rail/Signal/aspects_us_norac.html

you can see that when they say "Aspect" they mean the appearance of the signal as a whole, and they actually refer to "Aspect(s)" because there are various aspects that can all mean the same thing, and have the same "Name" which should cause the same "Indication". So for Rule 281 they show 9 different Aspects, all of which have the name "Clear", and give the indication "Proceed not exceeding Normal Speed."

So if you talk about "three aspect" signals what do you mean? Context suggests 3 heads, but it could be a searchlight capable of showing 3 colors, which would be correct use of the term "aspect", but that would only be a block signal, not an interlocking signal.

Unfortunately the western railroads don't use pure speed signaling the way we do in the east, where the NORAC rules are most common. I made a quick search for a signal chart that might be used in the west, but didn't come up with anything. Supposedly the western roads use "route signaling" but often it seems to be just a difference in terminology, so under NORAC an aspect of red over green, or green on the middle head of a 3-head signal, or the equivalent with position lights, would be called "Medium Clear" but on BNSF it would be "Diverging Clear". In both cases that's usually what an operator sees when taking a branch off a main line, with a requirement for reduced speed. Maybe someone who really knows signals can say more about this.
 
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