My Coachmen Crossfit came with unreliable tank sensors. Garnet SeeLevel tank sensors integrated into my DIY camper monitoring system would be a big improvement.
My current monitoring system is centered around MQTT and Node-Red running on a Victron Cerbo GX and a Nextion touch screen, with ESP32's where needed for reading sensors and communicating between devices.
Options for integration include buying a SeeLevel control panel with any of Bluetooth, RV-C, or NMEA2000 interfaces, the latter two of which directly interface with Victron's Cerbo units and/or Raspberry Pi running Victron's OS.
Reading the sensors/sending units directly, without the Garnet control panel also seems to be possible - based on this post in a Raspberry Pi forum
, where one of the participants (Jim G) figured out how to trigger and read the tank sensors/sending units directly.
I bought a couple of SeeLevel sending units and successfully dummied up a test using an ESP32 to trigger and read the sending units and a circuit similar to the one designed by Jim G. in the Raspberry Pi forum. It's working on the bench with two SeeLevel sensors attached to a water jug.
It's too cold to work out in the camper, so I'll not know if it's reliable in the real world until it gets quite a bit warmer. In the meantime, I've rearranged my display to accommodate tank gauges (lower left corner):
I figured I could either use (boring) green bars to show tank levels, or an appropriate set of emojis.
My code and a description of the circuit are uploaded to Github
. To fully integrate the sensors, I'll need to modify my code to encapsulate the data into JSON formatted ESP-NOW packets, and come up with an algorithm to properly interpret the data (likely in Node-Red).
I'd also like to put a bit of protection on the 12v circuit feeding the sensors. I'm not sure how tolerant they are of voltage spikes and anomalies. I've no idea how to do that though.