I just recently learned of this project and would like to start automatically watering some plants inside my house based on soil moisture. I'm planning on buying a Raspberry Pi Zero, relays, moisture sensors and the Irrigation Hat once it's back in stock. I will also have a large container of water set up with pumps inside that will turn on whenever the moisture reaches a certain level to provide water to the plants.
However, I am not entirely sure what I need to do in order to power the pumps. I've seen the videos on YouTube where Angelo has some kind of breadboard and uses a power supply and step down regulators but I can't seem to get the exact details of how he does this. Since I am going to only be using minipumps (something like this https://www.amazon.com/Driew-Submersible-Water-Aquarium-Fountain/dp/B01FZ0ZOTQ) that are 12V I would think this would be pretty simple, but I am not experienced at all in buying a power supply and wiring it up somehow. Could someone give me a list of items I would need in order to get everything hooked up? I have micro USB cables to power the hat and Pi but I think I will need other things to power the pumps through the relays. Assume I have nothing, not even wires.
Ideally I'd like to do this without any soldering so the only time I've attempted to do this I was pretty terrible at it.
I am US based so I can get pretty much anything at Amazon or if there is a better option for brick and mortar stores I have quite a few available.
The 12v main power supply plus the step down to 5v is my favourite way to go.
Regarding the step down I'd suggest a couple of items which i personally tested and used:
They are rated 5A.
I used also the step down converters rated 3A, there should be no problem using them with raspberry zero.
Anyway I noticed that they tend to fail quite often. The two above has been there for years without problems.
I put together my fiancee's greenhouse using similar parts to these from Amazon:
https://www.amazon.com/gp/product/B07NR6FPN9/ref=ppx_yo_dt_b_asin_title_o03_s01?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B07ZQB6S3L/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
https://www.amazon.com/Dual-Position-Screw-Terminal-Strip/dp/B008X0NNEY/ref=sr_1_20?dchild=1&keywords=wiring+block&qid=1597731891&sr=8-20
That power supply comes with a wire terminal to connect wire from it to whatever, in this case the terminal blocks to bring 12V power to the block. From there, connect the 12V to 5V adapter to power your Raspberry Pi. Then you can also run 12V wiring off the block to go to your solenoids to power your pump.
You should have plenty of power from the power supply as it's a 60W supply and that pump only draws 4.8W. The converter outputting 5V at 3A = 15W however these types of converters are not very efficient so figure 80-90% efficiency it may draw up to 18W. Even if we round that up to a solid 20W (as I like to be super over cautious) you are still left with 40W to work with.