I stumbled upon Kyle’s video recently as I am trying to get into hydroponics. Living in a 3rd world country, we barely have access to devices locally or with Amazon, so I’m planning to order a bunch of them from aliexpress.
I wanted to check whether the list of components below make sense and allows for a automated set up. I can hack some code together to create custom inputs, but I am not as good with electronics, power, pins, etc. So I’d really love to have feedback from experienced DIYers!
Things I’m looking for: particular precautions for calibration of sensors, advice on interoperability, protecting components e.g. voltage issues, coding the custom inputs, etc.
I am not sure what the purpose of carrier boards is, or if I should have them. For the flow totalizer, I figured I could maybe handle it with functions in the back-end.
Looking forward to your advice, and sorry if those are newbie questions !
Here are some comments from looking at your list:
- The UART to USB is for if you are using the MH-Z19B carbon dioxide sensor. You can also just connect this sensor straight to the Pi.
- The Gravity pH and EC sensors with the ADS1115 have had extensive testing in Mycodo. See How to create a custom input with calibration using ADS1115 ADC and Gravity analog pH and EC sensors?
- There is a generic flow meter input that counts and converts the number of pulses from the meter to a volume, so the totalizer board isn’t necessary.
That’s great feedback. Thank you for your time !
I will report back on the set up once it’s up and running.
you might consider buying several (2-3) humidity sensors instead of 1, because sometimes in high humidity enviroments (especially when there is condensing humidity) the humidity sensors tend to saturate and then read overly high values. They usually recover after a few days in drier conditions, but sometimes they do not. I have a good experience with Sensirion humidity sensors SHT31 for example:
However the best humidity sensors have a PTFE membrane which blocks excessive moisture from getting onto the sensor membrane, I have to say that after purchasing Atlas scientific humidity sensor:
I’ve had consistent humidity readings even in high humidity enviroments and I highly recommend this sensor. It is quite cheap for the high quallity and robustness.
I second the recommendation for the EZO-HUM. It’s well worth the money since you never have to worry about it being damaged by water. It’s also very responsive and easy to setup.
Just an update on the setup and some lessons learned so far. I have not implemented all the parts yet, but I am getting ready to plant in the next few days.
- I had to improvise with locally available materials for a lot of the plumbing/piping.
- I skipped the grow tent, lighting, humidifier, fans and the power control box, since where I live (tropical country) we have sunlight for 12-13 hours a day and 15-25C temperature year round, and the system is sitting on my balcony (see picture)
- so far, I invested ~$700 and 4-5 man days. I have a significant amount of excess materials.
- I would recommend going with a PVC frame rather than making a metal frame from scratch. I’m not very good wih DIY, so my aluminium frame made from plain tubing is kind of wobbly and not very tight. Screwing the channels to the frame helped tightening it.
- I used a 255mmx255mm junction box mounted to the wall to keep all the electronics together. The LCD screen is embedded in the junction box
- I used 1/2in flexible hose pipes rather than microtubes for the water inlet. It was not easy finding adequate tubing, the grommets to secure it, and to have water flow equally across all channels.
- it’s important to have the right fittings to avoid leaks - my set up has a lot of heating, bending and taping things together since I couldn’t get matching threaded adapters, reducers, end caps, tees, etc.
- I procured 3V peristaltic pumps and I’m planning on powering them with the Pi. We will see how it goes.