Trains.com

Block Signal Wiring

3953 views
10 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    July 2005
  • From: Northeast Missouri
  • 869 posts
Block Signal Wiring
Posted by SchemerBob on Wednesday, May 23, 2007 8:56 AM

While I'm waiting to do something about my switcher, I've got another question, this one though is about my layout. When I expand it, I am planning on having real operating block signals on each main loop of track. The problem is, it seems like both Lionel and MTH have different ways of how to activate them. Lionel has the odd 153C contactor, and MTH has some special RealTrax trigger or something. I read in some book that you can wire up signals with insulated tracks and have actual "blocks" of track that the train occupies. This sounds like the best bet. Can you do it? Is there a way you can activate the signal with the insulated track and power it from another source?

Long live the BNSF .... AND its paint scheme. SchemerBob
  • Member since
    December 2001
  • From: Austin, TX
  • 10,096 posts
Posted by lionelsoni on Wednesday, May 23, 2007 9:06 AM

By far, the simplest scheme is one with two-aspect (red-green) incandescent-lamp signals.  It can be done without any relays or electronics:

Isolate one outside rail for the complete length of each block.  Connect that to the common terminal of the signal(s) guarding that block.  Connect the green lamp's terminal to ground (the track common--the non-isolated outside rail).  Connect the red lamp's terminal to the supply that you want to use, which should be returned to ground.  Connect a large-enough lamp or lamps in parallel with the red signal lamp so that the red signal is dark when the block is unoccupied.

You can use a hidden or covered lamp for this, or use some lighted accessory if you don't mind that it will light up whenever the block is occupied.

Three-aspect signals are much more complicated.  Two-aspect signals can also be more complicated if you want to use relays.

Bob Nelson

  • Member since
    December 2003
  • From: Baltimore, MD, USA
  • 263 posts
Posted by 4kitties on Wednesday, May 23, 2007 11:06 AM

Both of my mainline loops are divided into 4 blocks with a signal for each.  I use insulated track sections with all of the signals.  I do use relays but they aren't terribly complicated to wire and allow me to use an independent 12VDC power source for the signals.  So, yes, absolutely what you want to do can be done.  My signals have been in operation for about 3 years now and have given me no trouble whatsoever.

Joel

  • Member since
    January 2005
  • From: Lake Worth FL
  • 4,014 posts
Posted by phillyreading on Wednesday, May 23, 2007 11:18 AM

Scheerbob,

Don't know how to insulate Fastrac, wether you just leave out a pin or have to buy a special section of insulated track for use with Fastrac.  You may have to cut a connector under the track(on each piece if longer than one section) to insulate both outside rails and leave out the track pins at either end where you want to have an insulated section.

Lee F.

Interested in southest Pennsylvania railroads; Reading & Northern, Reading Company, Reading Lines, Philadelphia & Reading.
  • Member since
    December 2001
  • From: Austin, TX
  • 10,096 posts
Posted by lionelsoni on Wednesday, May 23, 2007 11:21 AM
If you wire the return of the signal supply to the return of the track supply (that is, the non-isolated outside rail), the signal supply may be just about any AC or DC supply that you wish.  If AC, it may be of any phase, frequency, or voltage, although I would hesitate to use more than about 25 volts for safety's sake.  I use +16 volts DC.

Bob Nelson

  • Member since
    December 2004
  • From: St. Louis, MO
  • 4,913 posts
Posted by Brutus on Wednesday, May 23, 2007 10:20 PM

http://www.oldies.com/product-view/4957GD.html

They show you how to do this on this video, plus how to alter sections of fasttrack and stuff.

RIP Chewy - best dog I ever had.

  • Member since
    February 2005
  • From: Near Atlanta, GA
  • 288 posts
Posted by luther_stanton on Thursday, May 24, 2007 6:52 AM

SchemerBob,

Signaling is one of my favorite aspects of modeling railroading.  It is satisfying to see a train enter a block and have the signals automatically change aspect.  It is pretty easy to do as well.

I have seen the light bulb in parallel suggestion previously but I am not a big fan.  Some may see it is embodiment of simplicity - it is inexpensive and has the desired effect.  However, I see it as the wrong tool for the job.  The 153C contactor you mentioned as well as the other Lionel IR type solutions are based on either an electrical or electro-mechanical switch.  Light bulbs were designed to light.  Relays were designed to switch.  I have found that matching the problem and solution as closely as possible typically provides a solution that is easy to implement, lasts longer, performs better and gives you more options for expansion.

If cost is your absolute driving factor, then use the light bulb.  However, my advice is to use a relay.  When I wired up my first relay I liked the result.  I then started getting more complicated.  As an example, on a passing siding I created some "OR" logic - I wanted the aspect to be red when the adjacent block or next block was occupied.  In another scenario I wanted the same block to drive multiple signals.  In still another area, I wanted to drive some crossing gates and the signals.  The more I added the more opportunity I saw.  While you may be able to do all this with a light bulb, the relay made implementation quick, easy, and consistent.  It was wired the same way every time.  Also I only needed on relay to do the job in each example.

You can use either an AC or DC relay.  I use both.  The DC relay is a little more work, a little cheaper and the components can be found at Radio Shack.  An AC relay can be purchased on line from an electronics supplier, or Scotts Odds n Ends (http://www.scottsodds-n-ends.com/p9-MTR-12T.htm).  I use 12V relays.

Most relays will have 5 connections - two for the coil and three for the switch.  In the AC example, one of the coil connections should be tied to 12VAC and the other to the insulated rail.  For the three contacts, one will be labeled NO or Normally Open.  That goes to the red aspect.  The NC or Normally Closed goes to the green aspect.  The third switch contact should be tied to 12VAC.  That is all there is to it.

The DC relay will require a bridge rectifier installed to drive the coil and will require some soldering if you use your AC transformer for power.  While a little more work, I turned these into mini-projects which also gave me some soldering practice.  I am current scratch building some line side sheds to house the small PC board I mounted these on.

For driving voltage, check the manufacturer's recommendation.  If I recall correctly, many of the Lionel signals call for 14 - 16 volts.  Powering the signals with a voltage on the lower end of the recommendation will provide a longer bulb life with minimal decrease in brightness.  I run all my signals off of a 12v supply.  The signals are not as bright but bright enough for me.  And they will last longer.  I suggest before deciding on any voltage, try different voltages on one your signals and select the lowest voltage that keeps your signal at an acceptable brightness. 

Let us know how your implementation turns out!

Luther Stanton ---------------------------------------------- ACL - The Standard Railroad of the South
  • Member since
    July 2005
  • From: Northeast Missouri
  • 869 posts
Posted by SchemerBob on Thursday, May 24, 2007 12:48 PM
 luther_stanton wrote:

SchemerBob,

Signaling is one of my favorite aspects of modeling railroading.  It is satisfying to see a train enter a block and have the signals automatically change aspect.  It is pretty easy to do as well.

I have seen the light bulb in parallel suggestion previously but I am not a big fan.  Some may see it is embodiment of simplicity - it is inexpensive and has the desired effect.  However, I see it as the wrong tool for the job.  The 153C contactor you mentioned as well as the other Lionel IR type solutions are based on either an electrical or electro-mechanical switch.  Light bulbs were designed to light.  Relays were designed to switch.  I have found that matching the problem and solution as closely as possible typically provides a solution that is easy to implement, lasts longer, performs better and gives you more options for expansion.

If cost is your absolute driving factor, then use the light bulb.  However, my advice is to use a relay.  When I wired up my first relay I liked the result.  I then started getting more complicated.  As an example, on a passing siding I created some "OR" logic - I wanted the aspect to be red when the adjacent block or next block was occupied.  In another scenario I wanted the same block to drive multiple signals.  In still another area, I wanted to drive some crossing gates and the signals.  The more I added the more opportunity I saw.  While you may be able to do all this with a light bulb, the relay made implementation quick, easy, and consistent.  It was wired the same way every time.  Also I only needed on relay to do the job in each example.

You can use either an AC or DC relay.  I use both.  The DC relay is a little more work, a little cheaper and the components can be found at Radio Shack.  An AC relay can be purchased on line from an electronics supplier, or Scotts Odds n Ends (http://www.scottsodds-n-ends.com/p9-MTR-12T.htm).  I use 12V relays.

Most relays will have 5 connections - two for the coil and three for the switch.  In the AC example, one of the coil connections should be tied to 12VAC and the other to the insulated rail.  For the three contacts, one will be labeled NO or Normally Open.  That goes to the red aspect.  The NC or Normally Closed goes to the green aspect.  The third switch contact should be tied to 12VAC.  That is all there is to it.

The DC relay will require a bridge rectifier installed to drive the coil and will require some soldering if you use your AC transformer for power.  While a little more work, I turned these into mini-projects which also gave me some soldering practice.  I am current scratch building some line side sheds to house the small PC board I mounted these on.

For driving voltage, check the manufacturer's recommendation.  If I recall correctly, many of the Lionel signals call for 14 - 16 volts.  Powering the signals with a voltage on the lower end of the recommendation will provide a longer bulb life with minimal decrease in brightness.  I run all my signals off of a 12v supply.  The signals are not as bright but bright enough for me.  And they will last longer.  I suggest before deciding on any voltage, try different voltages on one your signals and select the lowest voltage that keeps your signal at an acceptable brightness. 

Let us know how your implementation turns out!

Right after I started this topic, I looked on the internet and found many diagrams of how to wire block signals and crossing gates to insulated track with relays. It sounds difficult when someone is describing it, but once you look at the diagrams it really doesn't look hard at all. And, the good thing about it is that all I have to do is place insluated tracks. Then, I can add the signals I want in later. With FasTrack, there is track called "Accessory activator", which I think is an insulated track containing two isolated 5" pieces. After that, all you have to do is add more 10 " insulated pieces in between the isolated pieces, and boom...you have a block. Then all you have to do is wire your signal to the bottom of the track, and wire it up to the relays & stuff. I think this will work well!

Long live the BNSF .... AND its paint scheme. SchemerBob
  • Member since
    December 2001
  • From: Austin, TX
  • 10,096 posts
Posted by lionelsoni on Friday, May 25, 2007 9:18 AM

It doesn't look like I'm going to convert Luther.  And doing it with relays is fine for anyone who feels better doing it that way.  But I would like to point out the subjective nature of his aversion to the relay-less design:

He does admit to his credit that, "it is embodiment of simplicity - it is inexpensive and has the desired effect."  I thank him for that.  But I don't agree with him that a relay meets his criteria of "easy to implement, lasts longer, performs better and gives you more options for expansion" as compared to the parallel-lamp design.  There is clearly less wiring without the relay and no possible difficulty of finding an appropriate relay or modifying one with a rectifier.  The two schemes perform identically.  I'm not sure what the "options for expansion" would be with an SPDT relay; but it is perfectly possible to add a relay for some other purpose to a parallel-lamp circuit (with the coil in parallel with the red lamp), using the same control rail.  The only test in which the parallel-lamp circuit might not equal or excel is "lasts longer", in that there are three lamps to burn out eventually instead of two.  Luther's advice to underrate the signal lamps is also good advice for the third lamp.  However, replacing a lamp eventually should not be a serious maintenance problem.

So, if relays give you a good feeling, by all means use them.  But, as for me, I don't have any problem with gaining an advantage by using something for an unintended purpose; in fact, I get a kick out of it.  It's the electrical equivalent of using a tin can to model a water tank.

Bob Nelson

  • Member since
    March 2005
  • From: Southwest Georgia
  • 5,028 posts
Posted by dwiemer on Friday, May 25, 2007 9:34 AM
 phillyreading wrote:

Scheerbob,

Don't know how to insulate Fastrac, wether you just leave out a pin or have to buy a special section of insulated track for use with Fastrac.  You may have to cut a connector under the track(on each piece if longer than one section) to insulate both outside rails and leave out the track pins at either end where you want to have an insulated section.

Lee F.

Philly and others, the easiest method I have found for insulating Fastrack is to use a Dremel tool with a Diamond disk.  For center rail insulation, I just cut the rail about 2" from either end of the track section.  For outer rails, you can cut the rails, but also must remove the "bridge" from under the track section.  Very simple, the only thing to be mindfull of is that the dremel tool will try to take off, so make sure you have a steady grip and holding the track in place.  And make sure the rail is divided all the way down to track bed.

Dennis

TCA#09-63805

 

Charter BTTs.jpg

  • Member since
    December 2006
  • From: Powell, OH
  • 1,257 posts
Posted by Wes Whitmore on Friday, May 25, 2007 10:54 AM

I just used a grinding wheel and removed just enough of the rail end on my MTH track to not touch the next track section's rail. MTH has spring steel terminals under the track that connects to the next piece, and I just bent that back out of the way so they don't interlock anymore.  That way, I can use it again if for a normal piece of track if i need to.

Wes 

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

FREE EMAIL NEWSLETTER

Get the Classic Toy Trains newsletter delivered to your inbox twice a month