Getting My Feet Wet...
Updated: Jul 16, 2018
It's been a while since my last post, but I've put all my energy in getting the Aquarium project up and running. Having an empty fish tank in the house looks quite ridiculous, so I wanted to get it up and cycling as fast as possible. Given my ambitious plan to automate it as much as possible in order to have as little maintenance as possible, I had some waters to swim before getting to this point. My tank is cycling for 8 days now. (without fish)
This is what the automation part (built inside the closet the aquarium is sitting on) looks like when finished:
Everything in here is controlled by a Raspberry Pi. 6 channels (colors) of independently PWM controlled LED lighting (left), 8 channels of 220V relay, of which 6 are wired to a regular outlet, (and 2 wired and put into junction box for later use), a temperature/humidity sensor to check on any (water) problems near the electronics components, a MAX7219 LED display that shows aquarium values like water temperature, pH, NO3, a senEye device with custom python code to read the values directly from the usb bus. A noIR camera is also fitted. One more stepper motor control and 1 servo control will be added later on to power the automatic fish feeder I am building. I preventively brought the necessary (and last) free GPIO pins to the front of the breadboard for easier access.
Here's a better view on the 'ceiling' part where most of the raspberry (and the controller circuits reside:
In a next post I will try to tell the story of building the test-setup and the problems I've encountered. Here's a last view on the finished test-setup of the ceiling controller part, but with opened boxes (which is always a lot nicer).
To the left 2 junction boxes with each 3 MOSFET controllers/circuits and a separate 24V power supply. In the center the 8 channel relay (the one that I didn't blow up). Next to that we can seen the breadboard with the temperature sensor on there. I didn't bring the last free pins to the front yet on this pic. Lastly the raspberry itself (with cooling since it'll be locked up in a closed cabinet). Hidden behind the big junction box (with the Relay) is a car part, used to downstep the 24V DC from the LED PSU to 5V DC to power my 5V rail on the breadboard. The relay takes too much power to be powered directly from the PI. The LED display needs to be fitted to the cabinet.