About the dosing pump

A project log for Pool Monitoring and Sanitation

Measure PH, ORP, temperature, inject chlorine in a pool. Log all data wirelessly.

Discreet MayorDiscreet Mayor 10/24/2021 at 12:340 Comments

The dosing pump is very much a home-made thing (and it also requires a proper mounting enclosure!):

It currently consists of:

Nema 17 motor to electric outlet plate

There was already an ozone venturi injector for the pool, so I am tapping into that to inject the bleach. My 3D printed design attempts at a small venturi injector of my own were all unsuccessful, maybe because I tried making them too small.

Cross section of a failed venturi pump. Maybe if they were printed it bigger?

No specs are provided on the stepper motor, and I don't really trust the stated 1.3A rating, so the board is designed to run it at around 500 mA. I can get about 100 mL per minute, which isn't very much, but works well enough.