Hello @jdag ,
Those are good questions. I like good puzzles to think about, and trying find a solution.
- “How does the sensor actually get activated? Is it by water submerging the bottom part of the sensor, thus closing the circuit of the small silver probes? Or based on humidity or even splashes (in which case my idea would likely not work)? Has anyone tried this? How is it working out for you?”
Although I was unable to definitively find any written documentation on if it is water or humidity that triggers this sensor. But I did find this YouTube video and it is apparently just water completing the electrical circuit on the metal probes on the underside, that triggers the sensor:
https://www.youtube.com/watch?v=-f4PuHlH39U
I understand how a shelf in the pit, roughly 12" from the top, would give you early warning before it actually overflows. But it is a concern, because as the water continues to rise, could envelop the entire sensor. Ring states:
- _ Can the Flood & Freeze Sensor be submerged in water?
No. While the device is engineered to be air-tight, it is not meant to be submerged under water during normal operation._
https://support.ring.com/hc/en-us/articles/360021558531-Ring-Alarm-Flood-Freeze-Sensor-Information
Since “just water” on the probes completes the circuit, your idea of a shelf in the pit should work.
But as the water level continues to rise, it might submerge the sensor (unless it floats, since it is pretty much airtight). There is no guarantee that the sensor won’t get damaged.
Although that doesn’t mean if you dry it out that it won’t work. But on the rare occasion of an actual flood, maybe “sacrificing” the sensor is worth the warning benefits.
When you mentioned previously having a “float” in your last home, I had ideas of maybe how you could make a float-type device that has a vertical push-rod on top with a Ring Contact sensor-portion attached to the top of the rod as this sensor ‘sits’ on top of the magnet-portion that is fixed to some sort of bracket. As the water rises, eventually lifting the float & rod & Sensor away from the magnet, you would get a text-type Notification on your smart-phone. It should work, but could be complicated and difficult to build if you are not handy.
But then I watched another YouTube video, and another different and simpler thought occurred to me. What if you just attached wires to one pair of the sensor’s probes and dangled the other end of the wires about 12 inches deep into your pit? You could ensure the exposed bare wire ends are secured to maintain a small gap apart, and not touching any surrounding conductive material in the pit that would trigger a false alarm. When the water level reaches the dangling wire ends, it completes the circuit, and I believe the sensor would trigger. The wires are basically an “Extension Cord” of the probes and you don’t need to make a “pit-shelf.” You could do a little test experiment and find outif this works by just putting the end of the wires in a glass of water.
If only dangling wires are needed, your sensor could just sit on the floor next to the pit with your attached wires dangling into the pit to provide Early Warning detection. You wouldn’t have to worry about submersion issues either. And if the wire-extension cord fails to work (but I think it logically will work), the Flood Sensor is still right next to the pit to detect if it overflows. Here’s that YouTube video that gave me this idea:
https://www.youtube.com/watch?v=EoXgkEkTp1Y
Well John, hopefully I’ve written something that is helpful to you. If you try the dangling “Extension Cord” experiment, I’m very curious to hear an update of the results. 