TRAIN AUTOMATION
Since I do not particularly enjoy running the trains (the fun is in the building), I try to have all my trains run themselves. In order to accomplish this I created and installed electronic controls that sort of think for themselves. I got some help on the design from Matt’s Dad, Dick and our Florissant friend, Brian. They are much more knowledgeable in electronics than I am. The three main types of operational controls are as follows:
Independently Operating Mainlines
With the independently operating mainlines, I like to install circuits that allow the trains to stop in front of a passenger station, trolley stop (s) or freight unloading spot. The way this works is the train comes to a location and stops for a period of time (for example 15 – 30 seconds). The train then starts off and continues its run. This type of operation can occur multiple times on a single mainline.
· The parts
This is accomplished with the use of the reed switches, magnets, and a relay timer device, that interrupt the power to the track.
· The details
A magnet is glued to the bottom of the engine or first car following the engine. When the magnet passes over the reed switch, contact is made and the timer is set off. This in turn causes a relay to be energized and cuts current to the mainline tracks. After the timer’s time expires, the relay is released or no longer energized thus allowing power to pass through to the track.
Independently Operating Siding
With the independently operating siding, I like to use a small engine or switcher and one or 2 cars (usually freight). The way this works is that the engine and car(s) travel to one end of the siding and stop. They wait for a period of time (approximately 15 seconds) and then start to travel in the opposite direction. When they get to the opposite end of the siding they stop again, wait and then reverse direction. And so on!
· The parts
This is accomplished with the use of the relays, a relay timer device, and diodes that control the direction of power to the track.
· The details
Near each end of the track a cut is made and a diode is bridged between the 2 sides of the cut track. This allows the current to pass in one direction only. This method prevents the engine from getting current past a certain point and it does not fall off the end. The timer is set to allow for the time it takes the small train to travel the length of the track plus about 15 seconds. The timer controls a relay that alternately energizes and de-energizes (in other words opening and closing the contacts). The wiring on the relay is set up to allow current to pass to the track for one direction when energized and when not energized the polarity is reversed.
Sidings That Operate In Concert With Another Siding And The Mainline
Sidings that operate in concert with another siding and the mainline work as follows. A train moves in one direction and enters a siding. That train stops. Alongside this train is another siding with another train facing the opposite direction. When the first train stops, the second starts and leaves it’s siding and enters the main line. After second train makes a full circle on the mainline it returns to it’s “home” siding and the first train takes off again (entering the mainline) and so on.
This is the most difficult to accomplish, but it can be done.
· The parts
This is accomplished with the use of the reed switches, magnets, and 2 sticking relays that control the power to each of the two sidings and the mainline track.
· The details
In order to accomplish this each train
must be equipped with a magnet and each siding with a reed switch. This
is because each train must be detected when it reaches a certain point in its
“home” siding. When the train is detected in its “home” siding, it causes
one relay to be energized and another to be de-energized. Each relay in
turn controls the presence or absence of current flowing to a siding as well as
the direction that the current will flow to the mainline. The polarity or
direction of current flowing to each siding is fixed and does not change.
The switch tracks also need to change direction. This is accomplished by
using a homemade plastic rod imbedded in a wood block acting as a spring. When the train goes in its natural direction
(entering its home siding), the switch track does nothing. When the train is leaving its home siding,
the wheels cause the switch flanges to spring open allowing passage.
OTHER TYPES OF TRAIN AUTOMATION
Road Crossing Lights and Gates
Crossing signals are positioned where train tracks cross streets and roads. This usually consists of signal lights, crossing gates or a combination of both. As a train approaches the light signal is activated and flashes and / or a gate drops. When the train passes the lights stop flashing and / or the gate lifts.
· How it works:
This is very similar to the start and stop circuitry as described in the independently operating mainlines. A magnet glued under the train triggers a reed switch, which in turn causes a set of lights to flash or a gate to drop. When the magnet passes over a second reed switch, the lights stop flashing or the gate rises. Initially, I will just have “dummy” crossing lights and gates. This is not a high priority item.
Easy
Road Crossing Lights
I
have a number of crossing signal lights that flash all the time. These were non-working crossing signals in
which I inserted bulbs.
· How it works:
A homemade flasher controls all in one
section. Each bulb is wired to one side
of the flasher unit or the other.
Overhead
Street Signs
I made a number of overhead street and location
signs. They are circled in bulbs where
every other one turns on and off alternatively.
· How it works:
A homemade flasher controls all in one
section. Every other bulb is wired
together and then to a single line to one side of the flasher unit or the
other.
DISCLAIMER:
In all fairness I must confess that the above is based on work I did may years ago with heat delay relays. My friends are helping me re-design the logic using integrated circuits in conjunction with traditional relays.