 If you look at the track plan (left),
you will see how all five of the branch lines and Schnyder Yard come into and
out of Adobe City (click image to enlarge). With all this
action that goes through the interchange in front of Adobe Tower, we need a
system to control all of the trains.The initial integration of the system was
researched and installed by Robbie Diehl. As time went on the system was
expanded and improved and a fully automated system was developed.
We have developed three different computer programs for our signal system in
Adobe City. They are 1: Dispatcher on duty, 2: Operations (when we are running
an operation session on the railroad), and 3: Automatic. |
| Let me explain a little about each program. For
dispatcher on duty, which we use when there is high traffic (for example during
our meets), the dispatcher has control of all trains entering and leaving Adobe
City. By pushing one key on the computer keyboard for a train arriving or two
keys for the trains leaving the dispatcher can align routes and turn signals to
the appropriate indication. The computer performs a "check" for opposing traffic
and will not allow the dispatcher to route two trains into each other. In the
Operation modes, a lot of the "fail safes" have been removed which gives the
dispatcher even more control over traffic. In this mode it allows for moves that
are needed during operations, but not during a simple run. The last and coolest
is the automatic program. With this there is no dispatcher required to be on
duty. The computer, through track detection, knows when trains are arriving and
can automatically align the inbound route turning signals and switches to the
appropriate indication and alignment. The computer sees what traffic is present
and selects which train gets to proceed. When a train wishes to leave Adobe City
the engineer pushes one of five buttons, relative to which branch they want,
next to his departure track. This notifies the computer where a train is and on
which branch they wish to go to. When the route is clear the computer aligns all
switches and changes the departing train’s signal to green. |
click image to enlarge
|
| This photo (above right) shows the
electronics that are used inside of the Adobe Tower . The large rectangular
boards are IO 48 boards produced by Oak Tree Systems. (www.oaktreesystems.com) We use a total
of 7 of these boards to control 34 individual signals, operate 23 switches
machines, show track detection in 23 separate blocks, receive information from
45 push buttons, show switch alignment from all 23 switches and align numerous
routes. This may sound very complicated but the basic system is quite simple. |
 The second key to our system after the circuit board is the
computer software. Here is the track diagram that appears on the computer screen
(left) which is used by the dispatcher inside of Adobe tower (click
image to enlarge). The software that we use is Railroad and Company Train
Controller, found at
www.freiwald.com. The beauty of the software is it that it is a point a
click program. You design your track diagram by clicking on the track section
needed and place on the diagram. Programming each item is as simple as choosing
the item, i.e. a two color signal, placing it on the diagram where you need it
and then setting the properties. I will get into this shortly. |
 To control the switch machines that Al Ford talked about in the
previous article, we run 18 gauge 7 conductor direct burial sprinkler wire. We
use two of these conductors for the plug which plugs into the switch motor. We
use three conductors to connect the switch alignment circuit and the other two
for spares. If you look (right photo) you will see two magnetic switch relays
that are mounted to the turnout (click image to enlarge).
The magnet is mounted on the throw rod. This is the type of relay used in the
home security industry on doors. They are extremely reliable and cheap. When the
turn out is thrown the magnet moves activating the relay to show which way the
points are aligned for. If the correct indication does not light on the computer
screen we know that the points are not all the way over. |
 As Al Ford talked about in his
article we use a very short
pulse of DC power to activate the switch machine. The length of time that the
power is on is set in the property menu on the computer. We simply use two
relays (left) in the tower to switch the polarity of the power to the motor (click image to enlarge). |
 For each of the signals we again use 18 gauge sprinkler wire. We
use super bright LEDs for the lights, so it takes very little power compared to
bulbs. There is also the added benefit that they are longer lasting. We simply
put a resistor in line with the circuit on a small board made for this purpose
from Oak Tree (right) then use the software to control the signal (click image to enlarge). |
| So far we’ve discussed the outputs. The inputs of
our system are the track detection and the push buttons. Both of these,
obviously, are run to the input side of the Oak Tree boards. For track detection
we run 14-2 with ground direct burial wire. One wire is connected to each side
of the track. When the wires come into the tower they go into a board designed
by our electronics guru Bill Pardee (right). This board simply has a small
reed relay and drop down resistors. The resistors are used so we can "fine tune"
each block so it is not affected by water (it does rain once a year here in
Phoenix), or due to the length of distance from the tower to each block. The
relay simply sends a signal to the Oak Tree board by closing the contacts
telling it whether it is activated (train in block) or not. |
click image to enlarge
|
 The pushbuttons we use (left) help make our system engineer
friendly. Which pushbuttons are active is dependant upon whether we are running
in a dispatch mode or automatic mode. The pushbuttons once again are connected
with 18 gauge sprinkler wire. The pushbuttons allow the engineer to select which
route they would like when departing Adobe City or, upon return, to select the
freight or passenger route around Adobe City and then one of four passenger
tracks in the station or the main yard. |
| The software is very user friendly. Once you have
designed your track diagram and placed all of your items on the track, for
example signals, switches and track detection the programming can start. You
simply select any item and open the properties for that item. In the properties
menu you select items that can be affected by the item being programmed by
either choosing items on the right side of the properties screen or by using the
record function where you simply click on the affected items. Let’s use the
signal at the yard entrance (Engine Lead, just past switch 14) (see computer
screen image above) on the diagram as an example (see computer screen image
right). Selecting record mode, click on any other signal that would allow trains
on the same track. By clicking on them the computer is programmed so that this
light can only be changed to green if the other lights are red. You continue
programming this with track detection. Now the computer will not allow a train
to proceed from the yard unless the lights and track detection are showing the
correct color and no occupancy. Continue programming your other signals in the
same fashion. |
click image to enlarge
|
| The other main function of the software
is the aligning of routes. To program a route, pull up the property on the route
icon and click the beginning of the route and the end of the route and the
computer will program the correct switch alignments and signal indications for
the route. Once this is completed to operate the program if a train is inbound
simply select the in bound route by clicking on the route icon or the "hot key"
which was assigned and the computer does the rest. For a train leaving the
dispatcher simply selects a departing route and the track the train is on and
the computer does the rest. |
| This is a very good and reliable
system. Because of this the training of new dispatchers has been found to be
very easy requiring only a short amount of time. New dispatchers are generally
not shown how to access the edit mode to make changes simply to limit the number
of people who make changes, but the system is easy enough to use that they could
be should it be required. |
| I would like to thank other members of
the club, Al Ford, Jim Manley, Bill Pardee, Pete Pennarts and numerous others
which have done so much in helping to build our system such as digging trenches,
placing wire in the ground or providing feedback on how the system has been
operating. |
