Sorry my english, im use Google translator.
see the current consumption of the relay module input and the maximum load of the esp output. if the load on the esp output is higher then you can connect it directly. Whether the relay module can be controlled with esp 3.3 volts.
There aren’t really enough suitable pins on an ESP8266 to drive an 8-way relay and although your diagram shows only 6 of the relays in use, the downwards arrow implies that you may be adding more devices in future.
If you want to drive an 8-way relay you’d be better with an ESP32, or an I2C expander like these:
Also, I’d get a 5v relay board rather than a 12v one.
I think I’d also avoid the USB hub as a way of splitting the 5v power supply.
Is the WiFi hotspot going to be connected via an Ethernet cable? If not then I cant really see it’s value.
Pete.
Hello @PeteKnight only use 6 pins and is working
The wifi hotspot have a sim card is necessary because this gonna stay on a remoted area.
And if the water pumps and solenoid valve work on 12 v, its possible use a 5v relays?
So it’s really a cellular router?
I think you’re getting confused between the actuating voltage of the relays and the maximum load switching voltage/current.
The relay modules I use have relays which are capable of switching 10A at 240v and 10A at 30v. This is about the voltage and current rating of the load contacts, nothing else.
The coil voltage of these relays is 5v and the Vcc pin of the relay board requires 5v + DC.
Using this type of relay you’re less likely to ever expose your ESP’s GPIO pins to more than 5v (which they can tolerate without any issues), regardless of what you do with the JD-VCC pins on the relay board.
Pete.
I’m not going to comment on your latest image because it’s so far removed from what we’ve been discussing.
If you already have a 12v relay module and you’re happy with it then stick with it. I’m just saying that I always choose 5v relay modules because of the issues I outlined earlier.
Pete.
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Ok @PeteKnight i use the 12 v module, and is necessary use the mt3608?
And you think is better change the power supply to the Wi-Fi hotspot and the esp8266.
Why, what purpose does it serve?
What I said is that I wouldn’t use a USB hub as a 5v power splitter for these devices - it’s not an efficient way to do it and it’s one more potential point of failure.
Simply split the 5v output yourself to power the Cellular Router and ESP8266.
Pete.
Ok Usb splitter checked is a better solution.
The mt3608 was because i have afraid that the current that came from the pwm controller, fried the relay, if have some increase of energy(seriously i don’t have any formation in electronics).
I’ve moved this discussion to its own topic, as it has nothing to do with the original weather station discussion.
Pete.
I think the question is more about the circuit of the 12VDC that is being fed from the Solar Controller to the 12V coils and pumps. That is, do you need to add the mt3608 to stabilize the voltage as it could fluctuate from 10.7VDC (Discharge Stop Value) to 14.5VDC (Buck Charge Value). This will be dependent on the pump/coil itself. A stable 12VDC voltage would be good as it is what is recommended by those manufactures. Will the other voltages damage the parts, probably not.
The mt3608 may not be the solution though for a stable 12VDC with the parameters given, as it is a boost convertor. This means it is designed for boosting the voltage up. So while it would work for periods of time where the voltage is <12VDC, it would not work for the periods of time when the voltage was >12VDC. In your case you would want to look for a buck/boost convertor (e.g. THIS) that could handle both the over and under voltage conditions.
Personally I would probably skip it and just run direct off of the Solar Controller, but this decision is up to you, so proceed at your own discretion.
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I certainly wouldn’t use a voltage regulator for these 12v pumps and solenoids.
If you did then you’d probably need more than one, as the current spikes you see when solenoids and motors kick-in will almost certainly exceed what a single regulator can provide.
Pete.
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It might be worth putting fuses separately to protect the relays, but I wouldn’t put a dc converter in front of the solenoids and pumps.
Agreed. I use 12v resettable circuit breakers on my solar setup.
Pete.
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For the question about wifi hotspot and esp8266, just a cable like this is perfect for the job. 
