I just noticed this string and just thought I'd mention my setup. I got into smarthome stuff trying to find a way to track my sump pumps since we had one basement flooding in the past. I use a Konnected.io NodeMCU board for this. It is cheap, simple and I use it for 6 inputs and 1 output. I have two identical sumps at either end of the basement so this was a low cost option with lots of flexible inputs. They've been going for over 5 years now. He advertises them as a low cost alarm system, but I didn't have an alarm system and they are awesome for sump pump monitoring.
The output is connected to a 12V Honeywell alarm that we can hear if we are home. The 6 inputs are connected to 6 Amazon float switches arranged vertically on a PVC pipe down in each pit. The bottom switch is as low as I can get it and I use it just for a notification every 12 hours on my phone to tell me the pit has water. That lets me know to monitor the pits during the day. The next 4 switches are in the range of the pump going up or down. (There were 6 inputs and a 12 pack of float switched so thats what I did.) When it pumps, the lower of the 4 just will just register dry. And just after the top one of the 4 gets wet, then it pumps. That makes for a pretty picture of changing color icons as the water goes up and down and I can see how fast it is filling. The top (6th) switch is just below where the battery backup pump kicks in, and it lets me know there is an issue. If it closes, Alexa will also announce there is an issue and the output on the board triggers the alarm via Hubitat rule.
Another rule is triggered when the top of the four registers dry followed by the third switch within a few seconds. They only go dry that fast after one another when it has pumped, and this adds one to a counter variable displayed on my dashboard. There is a reset counter button on the dashboard as well to reset the values when the storm is over.
The newer Watchdog battery backup pumps also have a dry contact relay when they trigger, so that is fed to a different Konnected.io NodeMCU that had an open input in the same room. That will also trigger Hubitat Notifications and Alexa announcements. In case of power failure in the night, I do have a simple battery powered water alarm with a long probe. The probe goes down into the pit about the same height as the 6th float that triggers the alarm. I cut the wire on that battery alarm and mounted it up in our bedroom since we had some unused old thermostat wires that ran to our bedroom from the utility room. The flooded basement happened long ago in the middle of the night during a power outage when we didn't have a battery backup pump. That storm dropped 15 inches at our house and almost 30 inches in areas nearby.
Our sumps may only run during spring thaw (Minnesota) and about 5 thunderstorms a year. But for some of those storms, they may pump 100 to 200 times because we usually get at least one annual thunderstorm that drops 4 inches of rain or more.
