Switching and signaling

[asciibaron]

any one here using an interlocked signaling system.  i would like to add signals to my layout and am looking for a place to start.

-steve

[cv_acr]

My club is planning to have working CTC, ABS and an interlocking in various parts of the layout. Nothing started yet though.
We're working on a big extension of the mainline right now and the plan is to put in all the required signalling circuits immediately as the track is laid and wired. Part of the expansion will involve installing the interlocking at the junction where the extension meets the existing track. But, we're working on structure, benchwork and roadbed, and some of the hidden connecting tracks. We haven't started any of the wiring/electronics for the new work yet, as we've really only just begun on actual track.

[seusscaboose]

any one here using an interlocked signaling system.  i would like to add signals to my layout and am looking for a place to start.

-steve

what is your definition of "interlocked"... does it mean that the system communicates with other signals throughout the layout and blocks... or is it mor of an "interlocking" definition, crossing from track to track and having signals change in that block only?

i am curious... b/c i have a block system set up at my house and i wonder how hard it would be to add a basic signal system (driven off block detectors).

EP

[asciibaron]

the signals and switches are connected so that no conflicting movements can be made - assuming there are no trains in the blocks, if a route is set against eastward traffic, the first signal to the west would have a STOP aspect, the next signal west an APPROACH aspect, and the 3rd signal west a CLEAR aspect.  when the route is no longer set against eastward traffic, the 1st and 2nd signals to the west would change to CLEAR aspects. .

i am trying to recreate the tower structure that existed on the PRR's Panhandle between the west portal of Gould tunnel and Frazeysburg, Ohio in the 1960's, a distance of 96 miles.  there were 7 towers and 12 remote controlled locations plus numerous distant signals between those points.  my "big idea" layout will have 4 towers and 6 remote controlled locations and distant signals as required.  each tower will have a US&S styled panel to control the crossovers, sidings, and signals within that tower's segment. 

my current layout represents 1 tower and the 3 locations it controlled (Morgan Run, Wally [WV], and Clow).  current sensing block detection is probably the easiest to implement, so i would have to chop the layout into blocks. i already intend to switch to metal wheels, so i could make the system foolproof by adding SMT resistors to each car. 

the tower system eliminates the need for a dedicated dispatcher and puts control of the layout in the hands of the train operators - this makes 1,2, or 3 person operating sessions doable.  the biggest pitfall is not having a single person deciding which train has priority, but with a 2 track main and several sidings, i don't think it will lead to a mega-merger sized meltdown.  each train operator would have to co-ordinate movements with the trains in advance and behind them - basically becoming the tower operator when their train is within a tower controlled segment.

i think that makes sense.

-steve

[Iain]

As long as egos don't get in the way, your operation scheme should work.

To get the interlocking to work, you need a switch on each turnout.  I assume you will have a signal controller for each signal.  Output from the turnout switch should be logically ORed (so as to not set the wrong signals) with output of the block detector for that block.  The output from the ORing should then go to the input of the signal control unit protecting the turnout.

[Skip]

Steve,

If you want to do only what you first paragraph says, a Digitrax SE8c and the JMRI softwars will handle it easy.  I had it working on my previous layout.  You need some type of block detection (I used Digitrax BLD168 for that) and position switch (es) on the turnouts.  I used Tortoise and one of its contacts for that. 

Now, if you want the train to stop at a red aspect, or slow for a yellow aspect, it is a bit more complicated, but still doable with the same hardware and a few additions (relays, etc).