Morton MC30 Water Softener HC-SR04 Ultrasonic Salt Level Distance Sensor Bracket

Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4322106.

This is a bracket for mounting an HC-SR04 ultrasonic distance sensor inside the salt well of a Morton MC30 water softener. This is part of a Home Assistant integration project.

This first version is minimalist. There is no cover yet designed, and the ESP module (ie, Wemos D1 Mini) has no set mounting space. There's still plenty of room for you to adhere one with foam tape. I plan to make a future version that has mounting accommodations for a D1 Mini or NodeMCU.

Sensor measurements in my tank are (+/- 0.01m): Level 0: 0.82m Level 1: 0.74m Level 2: 0.66m Level 3: 0.58m Level 4: 0.50m Level 5: 0.42m Level 6: 0.34m Level 7: 0.26m Level 8: 0.18m

In my experience, filling from level 0 to level 8 is almost exactly 160 pounds of salt pellets (Diamond Crystal brand). Therefore each level increment equals about 20 pounds of salt or about 0.08 meters.

Example HA / ESPHome yaml coming soon!

~1 year update: Unfortunately I never got around to designing a full cover for it, and the salt eventually took its toll on the contacts between the Wemos D1 mini and the ultrasonic sensor. Next time around, I'll probably place the D1 mini inside the softener control housing, run wires from there, and cover up the circuitry of the ultrasonic sensor as best I can with silicone sealant.

This thing was made with Tinkercad. Edit it online https://v1.tinkercad.com/things/gvvtS5NGuSh