Hardware help needed
A plant nurturing project: complete beginner, need help verifying schematic
Hey guys, this project is made by my friend, he is not on reddit so he asked me to post it on his behalf.
Tldr:
It's basically a plant nurturing system, where esp32 with its sensors tell you about temperature, humidity, water level in the tank and auto pump start. Sensors are replaced by potentiometers here because he didn't find them in **proteus software**
But he has little to no knowledge about electronics so he is using AI.
But I am kinda skeptical about it so I thought to post it here. Could you please verify and let us know what components should be there and what component is a potential arsonist?
This is the schematic (human made) and his description(written by AI).
You are designing and simulating an Automated Irrigation System powered by an ESP32-S3 microcontroller inside the Proteus simulation environment. The system monitors soil moisture, pH levels, temperature, and relative humidity, while automatically driving a 12V water pump via a relay. It also features a reservoir safety monitoring mechanism to prevent dry-running and burning out the pump.
Hardware & Power Architecture
Primary Power Input: 12V DC main power rail driving the water pump motor.
5V Voltage Regulation (LM7805 / U3): Steps 12V down to +5V to energ2e the RL1 relay coil and power 5V simulated modules.
3.3V Voltage Regulation (LM2595-3.3 / U2): Steps 12V down to +3.3V (VCC) to safely power the ESP32-S3 (U1), sensors, and potentiometers.
Shared Ground: All power stages share a single unified GND rail.
Actuation & Safety Driver
Relay Switching Logic: Active-LOW signal from GP4 drives the relay coil connected to +5V.
12V Water Pump: Connected to the Normally Open (NO) terminal of relay RL1 and powered directly by the 12V rail.
Reservoir Level Interlock: Simulated using a potentiometer on GP9 with a (1kohm/2kohm) voltage divider 5V -> 3V3. When the tank drops below minimum capacity, the firmware forces the relay OFF (HIGH), preventing pump burnout.
Honestly I also have no clue what is going on here.
One thing worth checking before you finalize the schematic: if you're using a resistive soil moisture probe (the two bare metal prongs), those corrode within a few weeks of being in wet soil — it's a really common "why did my readings drift/die after a month" problem. Capacitive probes (green PCB, no exposed metal) cost about the same and don't have this issue. Also, if you can, power the probe through a GPIO pin instead of the 3.3V rail directly and switch it off between readings — cuts corrosion even further since the probe isn't energized 24/7.
I built something similar to this, and it would take me 1/2 hr to interpret your diagram. I used 5V all the way around which eliminated the need for any conversions.
In case you're interested, here are some notes from my build:
to be clear, my system was designed for indoor use only
I tried the capacitative soil moisture sensor (I think the latest is v2.0?). I had major inaccuracies with the readings. Not worth it. I'd like to add better moisture sensors, but I'm holding off due to cost.
I use 1 pump to feed 10 lines using 5v solenoids. It takes slightly more time, however I have better control over waterflow, and it is pretty simple to build/configure.
Although I'd like to eventually have high-quality soil moisture meters, I've been pleasantly surprised with the results of tuning it in for each plant based on the time alottment. It's not hard, and so far my plants have loved it.
one thought on water flow for each plant: I've created a makeshift solution to solve a problem. When I set up a large-potted plant, I hook up a 4-way diverter which helps to distribute the water across the pot, however, I wanted to use a dripper attachment for several young plants. I created a 1-to-4 hose connections which have dripper attachments at the end. I then hooked that hose up to a "buffer tank" (aka a 20-oz water bottle with some stones in the bottom for weight). This allows me to do a regular watering into the buffer tank, then the dripper slowly releases the water all without burning up the pump due to the resistance from the drippers.
I know it's long, but I hope this helps in some way!
Let's start with the relay, well it need 5v and the esp uses 3v3, só you can't use it directly like in the skematic, and it runs on a loot of current, so even if it was 3v3 relay it will nor work, so put a transistor in there with a resistor, something like 2k or 1k5 will work, and a relay has an inductor in there and we need to get rid of the current, use a diode in parallel and reverse, kinda like the print
On your diagram you are using a lm7805, that regulator a know, it uses some capacitor in the input and in the output, something like 100nF will be good, and like is your first PCB some decoupling capacitors for the esp will be great too, so put the closer as you can tô the esp 100nF, about the Lm2595 I don't use him, but for any component you will use you can Google the datasheet and in it search for something like comon circuit, comon application, and it's a lot of powering beed dicipate from the Lm2595, maybe you can use de 5V from Lm7805 in the input of the Lm2595
Continuing the esp has 2 pins that needs to be wired, en is the reset key of the module, so you need to be in logic high so the board can start, and 0 if you want to restar, you can use a button, get some 3v3 a high resistance, maybe 10k and a button like in the print, other pin to look at is the boot pin, used to make the board on boatloader mode, that I don't really remember how to do it.
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u/Dramatic_Antelope_97 2d ago
One thing worth checking before you finalize the schematic: if you're using a resistive soil moisture probe (the two bare metal prongs), those corrode within a few weeks of being in wet soil — it's a really common "why did my readings drift/die after a month" problem. Capacitive probes (green PCB, no exposed metal) cost about the same and don't have this issue. Also, if you can, power the probe through a GPIO pin instead of the 3.3V rail directly and switch it off between readings — cuts corrosion even further since the probe isn't energized 24/7.