Some questions about signalling please.

[bn-1000]

Hi all,

I am in the construction phase of a long switching layout which has a dual mainline running through it from one end to the other. Off this dual mainline are two industries and a small classification yard.

At each end of the mainline I think it's appropriate to add some form of signalling to give the 'impression' or 'illusion' of the mainline continuing beyond the layout (at both end the mainline 'disappears' under road overpasses).

I was looking at the BLMA signals but should l use Block Signals or Searchlight Signals?

My understanding is that the block signals are indicating the status of the next block (i.e. the imaginary 'next block' which appears outside my layout at either end) so they sound more appropriate.

I am unsure where a Seachlight Signal would be utilized. Could I use a searchlight signal at the entrance/throat of the yard?

Any help of clarification would be appreciated.

 

[otiscnj]

I'm not a signaling expert, but I believe that Searchlight signals are just another type of block signal, as they both are used to show traffic ahead. A 'Searchlight' signal typically can show different aspects using a single light(or LED), where as many 'block' signals use 3 lights for 3 colors. If you google 'searchlight signal,' you may find that its a patented type of single that used to be offered by only one manufacturer(like Union Switch and Signal, vs General).

 

[D&J RailRoad]

What do you plan to use to run the signal lights?
How many signals do you plan on installing?
Single or double track?

 

[fcwilt]

Different railroads used different styles of signals.

Here is one brand of signals - you can see some of the various styles that are available:

http://www.tomarindustries.com/signals.htm

Here is a site with some information:

http://www.railroadsignals.us/basics/basics2.htm

 

[Iron Horseman]

My understanding is that the block signals are indicating the status of the next block (i.e. the imaginary 'next block' which appears outside my layout at either end) so they sound more appropriate.

I am unsure where a Seachlight Signal would be utilized. Could I use a searchlight signal at the entrance/throat of the yard?

It is just a matter of terminology. One is a term for a type of device. The other a term for its usage.

A searchlight is a specific type of signalling device as opposed to other types such as a semaphore, multi-light signal, dwarf, etc. Sometimes they are called "target" signals. As near as I can tell it depends on the manufacturer and/or railroad. That same signal device be it a semaphore or searchlight or whatever can be used for block indication, turnout indication, CTC instruction, crossing guard, station stop, or anything else an engineer might need for instructions and the safe operation of a train.

The Rock Island main out side of Wichita KS toward NM used an interesting (and ugly) triangular multi-light signal type. Don't even know what to call them. The advantage of a multi-light signal is that the position of the illuminated lamp carries meaning. This allows color blind people to be trainmen. A red-green color blind person cannot tell the indication of a single lamp target signal. That is why automobile traffic lights are always positional.

 

[dave1905]

Hi all,
At each end of the mainline I think it's appropriate to add some form of signalling to give the 'impression' or 'illusion' of the mainline continuing beyond the layout (at both end the mainline 'disappears' under road overpasses).

First is it two main tracks (traffic moves on signal indication in both direction on each track) or is it double track (traffic moves in one direction on signal indication on each track)? Different signal arrangements.
Normally absolute signals are at crossovers junctions or major locations where trains enter or leave the main track.
Are you modeling CTC?

I was looking at the BLMA signals but should l use Block Signals or Searchlight Signals?

A search light is a design of signal, a block signal is how its used. A block signal can be a semaphore, search light, banjo, position light, color position light or multiple lights.

My understanding is that the block signals are indicating the status of the next block (i.e. the imaginary 'next block' which appears outside my layout at either end) so they sound more appropriate.

I am unsure where a Seachlight Signal would be utilized. Could I use a searchlight signal at the entrance/throat of the yard?

A searchlight can be used for almost any type of signal. The signals could be on the main track at the yard throat. Depends if you want the trains to enter or leave the yard on signal indication.

 

[bn-1000]

What do you plan to use to run the signal lights?

I plan to run the signals off the Tortoise motor switches.

How many signals do you plan on installing?

Two. At the end of each mainline to give the illusion that my module is one block.

Single or double track?

Dual mainline.

It is just a matter of terminology. One is a term for a type of device. The other a term for its usage.

A searchlight is a specific type of signalling device as opposed to other types such as a semaphore, multi-light signal, dwarf, etc. Sometimes they are called "target" signals. As near as I can tell it depends on the manufacturer and/or railroad. That same signal device be it a semaphore or searchlight or whatever can be used for block indication, turnout indication, CTC instruction, crossing guard, station stop, or anything else an engineer might need for instructions and the safe operation of a train.

The Rock Island main out side of Wichita KS toward NM used an interesting (and ugly) triangular multi-light signal type. Don't even know what to call them. The advantage of a multi-light signal is that the position of the illuminated lamp carries meaning. This allows color blind people to be trainmen. A red-green color blind person cannot tell the indication of a single lamp target signal. That is why automobile traffic lights are always positional.

Ah, okay thanks. I was misunderstanding the concept of a searchlight. I had always thought they were a simple red on/off only.

First is it two main tracks (traffic moves on signal indication in both direction on each track) or is it double track (traffic moves in one direction on signal indication on each track)? Different signal arrangements.
Normally absolute signals are at crossovers junctions or major locations where trains enter or leave the main track.
Are you modeling CTC?

Thanks Dave H. also for your clarification. Very well explained. I didn't think of the function of the mainline (double track or two main tracks) so I'll probably lean towards two main tracks. For that setup I only require one set of signals at each end.

I might look for a dwarf signal to be placed at the entrance of each spur.


For the record my layout is freelanced but based loosely around BN early 1990's somewhere across the northern states.