Prototypical Grade Crossing Signals
By Don Woodwell
(excerpted from Automating Your Model Train Layout, 2nd Edition)

“Operation Lifesaver” is a national, non-profit education and awareness program dedicated to preventing tragic collisions, fatalities and injuries at highway-rail grade crossings and on railroad rights of way through public education, law enforcement, and grade crossing engineering.

Their statistics show that:
• Most collisions occur with trains traveling under 30 mph
• During daylight hours 64% of all collisions occur within 25 miles of the driver's home
• Approximately every 2 hours a collision occurs between a train and vehicle or a train and a pedestrian
• Nearly 50% of all collisions occur at crossings equipped with automatic warning devices
• Motor vehicles running into trains account for 24% of all collisions
• You are 40 times more likely to die in a collision with a train than in a collision involving another motor vehicle.

Operation Lifesaver offices are maintained in many cities, and you can learn how to present OL principles, warnings, and guidance to your community by attending a one to two day class sponsored by OL.

Upgrading your model train layout grade crossing signals doesn't require OL authority, but by doing so your layout's citizens will be more protected wherever a train crosses a road.

The use of scale-sized grade crossing signals for prototypical operation of train layouts has grown over the past several years largely due to miniaturization of components and demand by O-scale modelers. Scale grade crossing equipment like flashing lights, moving gates, ringing bells, and electronic detectors and controllers as well as installation techniques will be described.

Lights

A crossbuck's flashing lights scaled to 1/4 inch are a realistic 9.5 feet in height above the highway surface. If your layout’s main highway needs extra protection and warning, a cantilever signal may be seen further away by vehicle drivers since its lights flash at a 20 foot scale height. Both crossbucks and cantilever signals utilize long lasting and very bright light-emitting diodes (LED) whose alternating flash is controlled by an electronic flasher circuit.

Figure 1: Crossbucks and Gates Warn Road Traffic about Trolleys

Motion

Moving grade crossing protection devices include crossing gates or moving crossing gates with flashing lights. The activating mechanism for a scale-sized gate is located under the layout’s surface. For example, you could raise and lower a crossing gate with CIRCUITRON'S slow motion Tortoise™ switch machine equipped with their 'Remote Signal Activator.' Another slow motion switch machine made by Lemaco could be mounted vertically underneath the gate to raise and lower it.

Sound

Ringing bells add a third dimension to the well-protected grade crossing. Soundboards are very familiar to train layout operators today, and the crossing bell is no exception. Many firms offer a digitally recorded bell while CIRCUITRON also supplies a board to activate a real mechanical bell.

Detection

Prototypical activation of any crossing device requires a train detection method such as insulated rail, current sensing, infrared, or opto-electrical as previously discussed. When the train is detected, an electrical circuit is completed that turns on lights, rings a bell, or lowers crossing gates.

Electronic Controller

Detectors feed an electrical signal to a controller whose task is to activate the crossing protection equipment. A controller output flashes the LEDs on the crossbuck or cantilever signal, rings the crossing bell, or starts the crossing gate motor.

Figure 2: Generic Grade Crossing Wiring Diagram

Each detector and controller circuit supplier executes its designs differently so it's advisable to study their technical documents before buying their products to ensure that you are buying the right product for your grade crossing requirements.

The previous diagram shows a single mainline track, but your highways may cross a double or triple mainline or perhaps a mainline and siding or you may have a unidirectional mainline with multiple crossings. Each of these situations requires a different configuration of detectors and controllers not to mention multiple crossing protection devices. As such, pre-planning your grade crossing electronics is essential.

Installing the Components

Simulate a concrete base by mounting each signal on a 1” (2.54 cm) diameter dowel about ¼” to ½” in length, painting it with a concrete color, and gluing to the layout's surface. When this glue is dry, drill a hole in the base for the crossbuck or cantilever signal’s wires and gate’s activating rod. Add a spot of glue to the signal or gate base after feeding the LED wires or rod through the hole.

If you mix several suppliers’ components like signals, gates, and electronics, you should diagram the complete installation based on the separate instruction sheets. Subsequently, fax a copy to the suppliers for their approval. It’s best to get the connections right the first time rather than trying to debug errors when you find the equipment doesn’t work after it's installed.

In order to protect the components from dirt, dust, and damage, I mount them in black plastic “project box” purchased at Radio Shack, and use color-coded wires to facilitate connections to the track, crossing devices, and the other electronics. Mount the plastic box's cover to the underside of the layout either with screws or double-sided tape after the electrical components are mounted to it but before wiring the devices. Figure 3 shows a typical grade crossing installation under the layout surface. This is the physical installation of the Figure 2 wiring diagram, and the controlling modules for Figure 4.

Figure 3: Grade Crossing Wiring & Electronic Components

The black plastic base holds the controller and detector boards. A
crossing gate motor is on the right, and the TB routes power to the boards.

Carefully connect wires between the CEMs and power supply to the flashing lights, moving gates, and ringing bells to ensure that they work the first time. You should recheck the connections several times to make certain that they are attached according to your approved diagram.

I mounted the grade crossing ringing bell speaker in a bunkhouse near the crossing by gluing a two-inch speaker and sound tube to a cutout sidewall and hiding it with a cloth speaker cover in a color the same as the bunkhouse exterior wall. Visitors have no idea that a speaker is housed in that little building once it is landscaped. The soundboard is mounted under the tabletop as described above.

Test the completed installation by running your trains over the detection points and check the operation of each function. Assuming all wires are connected properly, all devices and functions should work. If they don’t, note what is not working, recheck each wire, and test again. If you still have difficulty call the supplier for his suggestions. When it's all working properly, glue the project box to its cover so that all the electronic components are fully protected.

Line Side Details

Integrating the grade crossing scene into your layout with added line-side details adds greatly to its realism. In addition to detailing the physical grade crossing, you may wish to add scale-size battery vaults, control panels, and sheds to house the controls. Figure 4 shows the gates, cantilever signals, bunkhouse, and line side details.

Figure 4: Finished Grade Crossing

Summary of Grade Crossings

Model railroaders who want a more realistic layout and high-rail operators should consider enhancing their highway grade crossings with light, motion, and sound for prototypical operations. State-of-the-art commercially available electronic modules make the upgrading easy and realistic, and the results are clearly worth the effort. But to top it all off, you can adopt Operation Lifesaver guidelines for the safety of your citizens.