Troubleshooting Tips

Infrared Detector Troubleshooting

How can I tell if my Detector is working before I install it?

You can check your Detector with a 9 volt battery. Connect the BLACK wire to the negative (−) battery terminal; the RED wire to the positive (+). Hold your hand 3 inches in front of the LED/Sensor or point it at an object. The yellow Detection LED on the wire end of the Detector should light.

Battery Hookup

Use a 9 volt battery to test your Detector before installing.

LED Glowing

LED will glow when an object is detected.

My Detector is installed and the Detection LED lights up when a train is passing. How do I check the Detector outputs?

The glowing Detection LED shows that you have physically installed the Detector properly and wired to Power and Ground correctly. To check the Detector outputs, disconnect the outputs from any other electronics and use a voltmeter to check the voltage between Ground (BLACK wire) and the Detector outputs:

  • When the Detection LED glows, the Detect High (BLUE) wire will be at the power supply (RED wire) voltage, and the Detect Low (YELLOW) wire will be at 0 volts.
  • When the Detection LED is off, Detect High will be at 0 volts and Detect Low is an open circuit. As an open circuit, Detect Low voltage cannot be predicted.

    (Applications using Detect Low will have a pull-up resistor in the connecting circuit to ensure Detect Low is at a high voltage when no train is present.)

Be sure to allow 2 seconds for the response from a Delayed Response (red jacketed) Detector.