Help with esp32 + 4CH relay 12v + PC Fan 12V

Maerka · May 28, 2022, 6:58pm

Hello!

I am having a hard time understanding what is happening here, I don’t know much about electronics, been learning by myself and playing with the wiring/coding as many others here

Here is what I have :

Esp32 + USB 5V power supply
Relay 4 Channel 12V
12V PC Fan’s
12V power Supply

The examples I have sawed in many websites are with a 5V and no external power needed, In my case using computer fans I think I will need the extra 12V power supply because the ESP32 can’t power the 12V fans (correct me if I’m wrong pls)

I have been trying to wire this with 2 different power supply (I have 2 to test with) and also different wiring positions and I think I have burned some fans trying because they smell like fried and if I connect them directly to the power adaptor won’t work now, so now I have tested the ones I have, and I have others that still work

The first power adaptor in the labbel puts :
AC ADAPTOR
Model no : AA-121A2
Input: 120VAC 60hz 20W
Output: 12VAC 1.2A
class: 2
note: In this one I can find easy the positive(red) and gnd(black) using a tester

The second power adaptor:
Switching Adapter
model: DSA-12CA-12
Input: 100-240V~ 50/60hz 0.3A
Output: +12V 1A
note: both cables show positive when testing , I think it is related with the AC DC type (?)

I think the first one will work better and have more power , one doubt I have is that the power adaptor says AC and the computer Fan say DC , will this be a problem ?

This is the diagram that I think should work since that’s how the examples I saw on most websites

But also I found this one ( But didnt work

)

I feel it is something related with power because I don’t hear the click on the relay when I click on home assistant switches to enable relay channels , I see the light/led under the relay board turning on and logs under ESPHOME are fine too(sending ON and OFF states), so the code and the integration is working fine.

I can’t get the fans to turn on or control them

Give me some ligth here pls

nickrout · May 28, 2022, 9:38pm

I believe the relays in the first pic ~~require 12v to switch the relay~~, you are supplying only 3.3v with the esp32.

EDIT not so sure that is so now.

Maerka · May 29, 2022, 1:21am

Thanks! I had that question but didn’t know if that will burn the board , we’ll now with you answer I have 2 questions

there are 3 VCC pins on the relay board ( 2 pins under the jumper VCC and JD-VCC, the last VCC is on the relay header) on which pin do I have to add the power 12v cable from the power adapter?
Should I move the gnd from the relay to esp32 - to the Gnd from the power adapter or I can leave it as it is?

nickrout · May 29, 2022, 2:00am

You have two relay boards in your pictures, so what exactly is the board you have? And what is written on the relays?

Maerka · May 29, 2022, 2:22am

I have the first one , the one with 4 channels and jumper

The code :

esphome:
  name: test

esp32:
  board: esp32dev
  framework:
    type: arduino

# Enable logging
logger:

# Enable Home Assistant API
api:

# server            
web_server:
  port: 80


ota:
  password: !secret

wifi:
  ssid: !secret
  password: !secret
  
 # Optional manual IP
  manual_ip:
    static_ip: !secret
    gateway: !secret
    dns1: !secret
    subnet: !secret

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: !secret
    password: !secret

captive_portal:


switch:
  - platform: gpio
    pin: GPIO23
    inverted: true
    name: "switch 1"
    id: switch1
  - platform: gpio
    pin: GPIO21
    inverted: true
    name: "switch 2"
    id: switch2
  - platform: gpio
    pin: GPIO18
    inverted: true
    name: "switch 3"
    id: switch3
  - platform: gpio
    pin: GPIO26
    inverted: true
    name: "switch 4"
    id: switch4

nickrout · May 29, 2022, 3:49am

I really got a bit lost researching these relays! But I think I am right in saying that they should be powered by 12v, and the IN should be triggered off 5v (and should work with the esp32).

I would play around with some bits of wire and try triggering them rather than risking the esp32 GPIOs.

Maerka · May 29, 2022, 4:16am

Yep I’m lost looking at the examples that I have find , I want to know now in which pin I set the 12v , thanks for the help though <3

nickrout · May 29, 2022, 5:03am

Is there a voltage convertor attached to VCC?

Maerka · May 29, 2022, 7:34am

No , only the ones in the picture

gaz99 · May 29, 2022, 7:54am

On a similar one I have, the JD-Vcc pin is connected to one of the coil pins of all the relays.

So you need to connect 12V to that pin. You will need a common ground for your relay power and the 5V running the ESP.

rcblackwell · May 29, 2022, 12:57pm

If the information posted is correct, then the first adapter listed (used) is AC, not DC. Could explain the burned smell of the fans.

I don’t see how polarity of the leads could be identified with a tester. If a voltmeter was used, I would expect the meter to behave like the note listed with the second adapter, not this one.

Maerka · May 29, 2022, 11:44pm

Thanks for the reply guys <3

@gaz99
So you are saying The +12v line from the power adaptor goes to the JD-VCC pin on the replay board lile the next image , the next one I leave it empy and the one VCC from the relay header to the esp32 ?

@rcblackwell
About that yeah like I said ( dont know much about electronics ) I have used this tool (image) to test on both cables from the 2 power adaptors , on the first one the tool show me the +12V line and the other cable dont show any value just a litle ray (so for me that was the gnd/negative) but with the secound power adaptor both cables show +12V that what I mean on the first post

rcblackwell · May 31, 2022, 12:19pm

My advice, ditch that silly little gizmo and purchase a proper multi-meter.

Maerka · June 4, 2022, 5:04pm

Could it be something about the code ? I been testing and still not able to work this out

The only thing I notice is that if I change the red cable from fan on Normally Close(NC) to Normally Open (NO) the fan will turn on at power on but I wont be able to turn it off it will just spin , from home assistant I turn on/off and see the logs and led (from relay) turning on/off but nothign on fan

Any ideas ? thanks

Update:

I am now trying with a 1 channel 5V relay and I having the same result so im doing something wrong here…

this is how im connecting the new 5V relay :
Red led (power) turns on , and also the red led turns on when switching on from home assistant , but no fan spinning or relay click sounds, have tested the fan and it is working

Mikefila · June 5, 2022, 4:14pm

Are you sure that it is 5v could it possibly be 12v? 5v will light the led but not switch the relay. Do you have a multi meter? What is the voltage coming from the signal pin of the esp? An under sized power supply probably would have similar results.

Maerka · June 5, 2022, 9:58pm

Hey! thanks for the reply! , I made it work! finally ( the new 5V ) not the 12V , on this 5V it was the wiring ( I mess the fan cable position) , Yes I have a multimeter (also trying to use it more since I dont have the basic electronic theory I have to play with the little knowlage I have , thanks ) I will try to mirror the same wiring on the 12V relay but I suspect it wont work because the ESP32 not able to send a PWR signal (12V) from the esp32 to the relay I think I will need a convertor o something else here to make that work

Rolexgurg · July 25, 2024, 7:19am

Good day … wanted to confirm if you found a solution and what type of connection did you use … I’m currently trying to use the same 12v 4channel relay and I’m going through the exact same problem … I’ll be happy if you can help

apreick · July 25, 2024, 8:25am

I also have exactly this 1x relay
That didn’t work for me either => until I found this post.

I couldn’t find the post in a hurry but still had a screenshot

Two of the 1N4148 have worked

If you use the 2x relay module from the same manufacturer, it works immediately without any modifications