Esp8266 fan and thermistor

Hello everybody,

i want to use an esp8266 to control a 5V fan (from a 3d printer, link to product on amazon.it) and read the temperature from an NTC thermistor.

For the software part I don’t think I will have any problem, but electronics is not my best skill… So could you guys check if my drawing is correct?

I didn’t find any info about but are the 3.3V and the 5V pins in or out?

Wiring looks correct, but your relay module needs more investigation.
Do you have a link?

sure, this is the link https://www.amazon.it/gp/product/B07BVXT1ZK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

evetually can i just power the esp (by the usb port) and use a gpio to power on the fan? bypassing the relay?

You can’t use gpio to power something!

ok I thought that once the gpio is closed it provide the 5v signal or something similar… sorry newbie silly question…

And your relay module is not compatible with Esp8266, it’s good only for 5V MCU, like arduino.

It provides 3.3V signal. But just signal, not power for a fan. Max current draw from Gpio pin is ~12mA.

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thank you,

even if I will get the 5v to power the relay directly from the power supply and use the gpio for trigger it?

I also have some esp32 full size board like these (https://www.amazon.it/gp/product/B074RGW2VQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) are these compatible with the relay?

Noup.
Esp in 3.3V MCU.

You can use 3.3V relay module, 5V relay module with separate driver circuit, 3.3V mosfet module or just simple NPN transistor with two resistors.

https://www.amazon.it/kwmobile-Modulo-relè-canali-Arduino/dp/B01H2D2RI0/

Sorry I am lost a bit…

So I can’t use the relay like this?

sorry but what is the difference between the relay you linked and the ones I have?

It has separate 5V power pins and optocoupled (3.3V) input pins.

mosfet:

Transistor circuit:
transistor-switch

Thanks again for your time

so with mosfet can I wire like so?

EDIT: in picure in and out are inverted… I noticed just now, anyway OUT +/- to the fan, DC+/- to the power source

Yes. Correct.

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