I’ve installed 4 Dallee Trak-dt occupancy detectors over the last several months. After initially working fine for a couple of weeks, two have developed the problem of not clearing when a train leaves the controlled section. Removing the track power supply wire from the sensor still does not result in the signaled section becoming deactivated. The only way I can clear the detector is to cut power to the detector for at least 10 seconds. When power is restored the detector deactivates and the signal clears. I have tested both problem detectors on a 3’ section of track mounted on a board to eliminate any possible problems generated by the layout. They still fail to clear. Anyone else had this problem with Dallee detectors? The other 2 detectors have continued to work fine.
Have you tried contacting Dallee on this? It sounds like you’ve got a problem with the circuit. It’s not likely to be the detector.
i don’t have my instructions for the dallee detectors handy but i remember reading about a trim potentiometer that adjusts the units sensitivity. you may have to adjust it to desensitize it a little. i’ve got three detectors in use for about 8 months now and they work good. very sensitive for n scale as they trip as soon as one wheel of a loco spans the insulated gap. if this doesn’t work call dallee. they may be under warrantee.
Thanks for your suggestions. I have talked with Dallee a couple of times. Unfortunately, their recommended fixes have not worked. I have rotated all 4 detectors through all four signaled sections on my layout and through the 3’ test track I set up. The “good” detectors work in all settings and the “bad” detectors work in none, which leads me to believe the circuit is not the problem. I am getting full power (16.5v) from the AC source and full power (12V) out of the regulated DC power supply. I think I may need to send them back and let Dallee test them.
Given the rotation test results, I would agree that you’ve got bad detectors.
Thanks for coming back to give us the update. Keep us informed. It’s always nice to get that final data point on a problem.