Start Tree lights on wrong side

Tree is facing backwards 

Turn Tree 180 degrees

Both Tree and Display show on wrong side

Sensor is backwards

Turn Sensor Assembly or track piece 180 degrees

Car on inside lane occasionally registers on outside lane

Sensors located to close coming out of a turn

Move Sensor Assembly forward.

Sensors do not respond

"sensor"  and "lights" plugs are reversed

Switch the plugs underneath the Control/Display Tower.

Sensors behave erratic. Over sensitive/Under sensitive. Miscount/Double count etc.

The metal reeds inside sensors have become magnetized. This is due to "parking" cars directly over sensors for long periods of time i.e. over night.

Use degaussing tool or simply wait 24 to 36 hours. Do not leave cars in Staging Area when not in use.

Photo Eye LED's will not go off.

1. Photo Eyes are calibrated too sensitive.

2. Not enough ambient light in the room.

Turn calibration knob CW 1/8th turn after LED goes out.

Provide more light. Florescent light works best. A small reading lamp can be placed over the eyes for night racing.

Photo Eye LED's will not turn on even when calibration knob is turned all the way CC.

This condition  only occurs when eyes are in direct sunlight.  

Set up in the shade or you can make a canopy out of a shoebox to put over the sensors.

One side of Photo Eye Sensor will not calibrate. LED either says on or off continually thru the full range of calibration knob.

You have a bad photo eye.

Replace Sensor Assembly. Take care when installing not to let the crown of the photo eyes to protrude above the rails in the track enough so that low-profile cars might come into contact and damage the eyes.

Photo Eyes register multiple counts on a single pass or makes random miscounts.

Calibration is set too sensitive.

Turn calibration knob 1/8th turn CW.


           Set up tips when using photo eye sensors in Loop Track


  1. Install photo eyes in track.


  2. Power up the system. Ignore what the Display and Tree may do, we are only using the system to power the photo eyes at this time.


  3. If one or both of the LED’s on the Photo Eye Calibration Module are on, turn calibration knob(s) clockwise until they go off. Then, continue to turn an extra 1/8 turn clockwise so they will not be too sensitive.  If the controls are turned all the way clockwise and the LED’s will not go off, place a small reading lamp over the eyes just for trouble shooting purposes and recalibrate. Turn control counter clockwise until LED comes on, back off until LED goes off plus an extra 1/8 turn.


  4. Press the reset button.


  5. Run a few races to confirm operation of the system.


  6. Now go back and work on providing sufficient lighting to the eyes. Florescent lighting works best. A fifteen dollar shop light from Home Depot works great.


              Setting up a Drag Race Strip using Photo Eyes


  1. Install both sets of photo eyes in track (start sensor/finish sensor). The power light on the calibration module is over to one side so you can distinguish lanes one and two. MAKE SURE THEY ARE PAIRED UP PROPERLY.


  2. Only plug one Sensor Assembly into Display/Control Module.


  3. Power up System and follow the procedure above for calibrating photo eyes in loop track.


  4. Unplug first Sensor Assembly and plug in second Sensor Assembly. Repeat calibration procedure until working property using a small lamp over the eyes if necessary.


  5. Now install “Y” connect and plug in both Sensor Assemblies. Remember the photo eyes interact with each other.


  6. If any LED’s are on, pick either end of the strip to start calibrating the eyes by turning control clockwise until LED’s go out. If LED(s) stay on in full CW position, go to the other end of the track and start turning the corresponding control knob CW until LED(s) go off plus 1/8 turn.


  7. Run a few races.


  8.  If you had to add on extra light source, remove the source and start working on a permanent solution light source.


  9. Note: the eyes DO see infra red light. There are many light bridges available, and/or instructions to build one, on the web.

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