Sensa-Trak™
Installation Instructions
- Please read directions completely before beginning your installation.
- For best results, use filtered, regulated, DC voltage.
- Use the Power Supply Regulator Board for this application.
- DO NOT use the variable output of a throttle control.
Installation is very simple. The first and simplest method of installing the Sensa-Trak™ is to drill a hole in the center of your track between the rails and through the roadbed. Peel the paper backing off the plastic standoff. Position the diode in the center of the hole and press the standoff to the bottom of the roadbed. See Figure 1. The standoff and IR diode height is adjusted for ½ inch thick plywood roadbed with 3/16 inch cork.
Note: When in the presence of ambient light, make sure there is enough light on the white detecting diode. If not, the red indicator will stay on all the time. When this happens, you will need to use the IR diode bridge system (included), or increase the ambient light.
There are three wire connections on the Sensa-Trak II™, red, black, and white. The red wire is the positive (plus) voltage input. The black wire is the negative (minus) voltage input. The white wire is the output. The output will drive a relay, an LED, a signal control, etc. If you are using the output to control an LED, use a 1k ohm resistor in series with the LED. The output is at a positive potential, or high, when there is no train over the diodes. When a train is sensed, the output will go to a negative potential, or low. See Figure 2 for the connections to the Sensa-Trak II™
The second method of installing your Sensa-Trak™ is by using the infrared diode bridge system. Drill a 7/64" hole in the roadbed on each side of the track at a distance far enough not to interfere with passing rolling stock. Install the IR diode bridge system in the two holes, directly above the white IR diode on the PC board. Make sure the IR diode clears the tallest car that is on your system. Solder the red wire from the PC board to the red solid wire that protrudes though the roadbed from the IR diode bridge system. Solder the black wire from the PC board to the black wire that protrudes through the roadbed. (see Figure 3).
