That’s fantastic! I’ll give it a go tomorrow and let you know how I make out. Thank you very much.
Good luck. Remember before attaching anything to the ESP32 to check the volage between the GND and the wire that will attach to the GPIO pin just in case it is more than 3.1V that may damage the ESP32.
Thank you very much I will do that. Another question how do I graph it backwards, is empty it’s 7vdc full is 3vdc? And honestly I don’t care if it’s a graph or just something that changes colors on state change.
That’s the thing about HA. You can show it any way you want. You can have it send you a message to your phone or an e-mail when it fills to a certain point or light up an LED or flash some lights. It’s all down to the imagination.
How did this end up turning out? Interested in doing the same thing.
I’m still not totally done but I have redone the wiring a few times. Here is my semi final results. I will say I had sd card failure about a month in so I upgraded to a SSD. I also ordered one of the pi poe SSD hats that I’m still waiting for and I did decide that since the relays I used are able to be powered by poe so I bought a poe 12v trendnet switch and I ordered a 12v router I’m still waiting for but other than that I’m pretty thrilled how it turned out. I also ended up using the Shelly uni to monitor my tanks that seems to work pretty good. My pi and my Poe switch are going to mount on that din rail.
Looks good. For the tank monitoring. Are you continuously sending 12v to the probes of each tank or did you do something similar to the original panel where you had to push a button to get a reading? Do you have any pictures of the wiring to the Shelly Uni?
Yes currently i am. i have ordered 5 different bucks to drop it down to 7vdc but not a single one i have gotten has worked! i am waiting on one that another friend had good luck with. i do plan on setting up a relay to only power once an hour or on demand.
So, 7v was either the sensor value for full or empty right? How are you using buck converters to read a 3-7v sensor? Those buck converters need a stable input inorder to put out a stable output so, it cant fluctuate that much. It is a creative odea, I definitely respect the effort and trying! Its really not a great way to read a sensor if at all.
Did the tank have physical sensors at varying levels (High, Med, Low) or does it continuously output a voltage at whatever the water level is?
Theres a couple ways to do what you need but, it depends on if you need the full range 3.1, 3.2, 3.3, 3.4, etc,etc…7v or fixed values like this, 7v- High. 5v- Med, 3v- Low.
For whatever its worth, if at all. I recently installed these in a water fountain I made. They’re IR No-contact water sensors. Theyre “no contact” that just means they dont need to contact water/liquid inorder to work. Theyll work from the outside of things like glass, aquariums, etc or work submerged in water. Ive been really liking them. I use them as my secondary/backup resevoir overflow sensors to prevent overfilling when my auto refill kicks on.
They have a huge variety of liquid level sensors on their website as well.
I joined specifically for this topic. It seems I have a similar system - but the paperwork says 8v common. But I am struggling to wrap my head around how to get any useful readings.
Are you still wired to the panel buttons, or are you able to get constant voltage to the sensors? How are you wired to get any sort of readings? It seems I have to push the panel button to get any readings at the probe wires.
Any help you can offer is greatly appreciated.
Hey good evening. I used a buck to step down to 7vdc because that’s what mine was originally…I am currently still feeding them constant voltage all the time I have had a chance to install my relay yet but that’s my next step. My graphs on my dashboard only update every hour my plan is to schedule that relay to come on then take the reading and turn off. Love to see yours or hear that worked for you.
Any chance you can send me a sketch of how you have the buck and uni wired? Did you have to disconnect the existing RV panel buttons?
Edit: I originally said Esp32, but meant Uni. But would still love to know how you have this wired - my tanks are literally the last thing I don’t have connected - and for some reason, I just can’t wrap my head around it.
I can try to draw something up. no i did not have the buttons in the camper like most do mine was part of the smart system that was originally in the camper. so i put 12 v into the buck and i also powered the 4 shelly Uni’s from the 12 v. i took the 7vdc output from the buck and i connected all of the grounds for the tanks and uni together so it was common grounded. then i used the analog input of each shelly and connected it to the return wire of each tank sensor i have fresh, black and 2 grey tanks. i then connect the 7vdc from the buck to the common tank input from the originally wiring. i then just setup the shelly uni in has to monitor that analog input for voltage and set my parameters to 0vdc to 7.5vdc.
That’s my problem. I don’t have access to my common ground to all of the tanks. I have one wire going from my panel to each probe, and one wire each for + and -/gnd. Those are the only wires connected to my panel.
Gnd is common when all tied together. It’s not some “separate” connection.
You’re right, but if you read his post, it appears he’s back feeding voltage through the probe common “ground” and reading it at each of the probe “positive” leads. I would need access to that common wire.
On second thought, maybe I’m misreading. Do you have three wires going to each tank? You mentioned first connecting the 7vdc output to the tank grounds, then second connecting the analog input to the return wire and then third connecting 7vdc output to the common input wire.
That doesn’t seem to match the drawing posted above. I’m really hoping I can figure this out. Thanks.
I don’t see any “back feeding”, do you mean that you don’t have access to gnd wire?
I have access to my battery/common/trailer ground. But each tank has two wires going to it. I only appear to have access to one - the side with the voltage on it. The common wire between all the tanks - shown as the ground on the sketches above - I don’t have access to. If I feed voltage into each tanks wire that have access to, where do I tie the analog input.
It would make sense if I had access to the common wire to feed voltage through that and then connect each tanks non-common/individual wire to an adc/analog input. I assumed that’s what was done, but after rereading, I must be missing something.