Installed two transformers. One works fine. Other I set the 2 hour timer and it goes on and off two hours later, however, for some reason it turns on again during middle of night. It went on today at 5 am when still dark. Can't figure it out, and wondering if defective? Could a passing cars lights (which would be a long shot as its certainly not direct) potentially rest the unit to daytime? Or other ideas to remediate?
From what you've described, issues with the timing like this are typically either related to interference from ambient light as you mentioned or a faulty sensor. To test the Photocell device: (In daylight) 1. Test in the ON position first. 2. If the timer works in this setting then, set it to dusk to dawn setting; it should turn off after doing this. 3. You should then cover the photocell in complete darkness for anywhere from 5-6 minutes (using a towel or something that encompasses the entire device is recommended.) After this time, it should power on. (If you have a Slim Line style transformer which has the timer device built it, you would need to cover the entire face of the unit to properly test the cycling functionality.) If the sensor is ultimately the issue, we will be happy to help get it replaced for you - just give us a call at 813-978-3700!