Thank you!

I purchased the kit of 2 fans, I hope it will be enough

https://it.aliexpress.com/item/1005004053911701.html?spm=a2g0o.order_list.order_list_main.5.43e13696NJoDVy&gatewayAdapt=glo2ita

18 hours ago, wifi75 said:

 

Hello does the fan you installed above the inverter aspire air?

Indeed it does, essentially sucking the warm air out and creates a circulation or cooler air from the bottom.

Hi peeps, 

I got four of these fans to cool down my inverter and other items, my challenge now is how do I connect these to a 12v supply? If possible can i use adapters with 4-pin 12V to AC? Or should i cut off the connectors and just use +ve and ground to a power supply?

 

https://www.rebeltech.co.za/noctua-nf-b9-redux-1600-pwm-92mm-pwm-nf-b9-redux-1600p-case-fan.html

14 minutes ago, Jakac said:

I got four of these fans to cool down my inverter and other items, my challenge now is how do I connect these to a 12v supply? If possible can i use adapters with 4-pin 12V to AC? Or should i cut off the connectors and just use +ve and ground to a power supply?

You simply wire them to a 12V DC power supply; red to positive and black to negative. You can use the old style black connector blocks or anything of the more modern connector blocks. And yes, I snipped off the connectors that the fans came with.

Pimping the ride...

Why do something simply when you can over-complicate it? On my 8kW Sunsynk I'm going to use 4x 12V Sunon fans which have 3 wires - red, black and yellow. The yellow wire provides a square wave output proportional to the fan speed. I'm using this to detect if a fan is slowing down or has stopped using a small monostable electronic circuit which lights a green led if fan speed is ok or red led if fan speed is below a minimum. This way a simple visual indication tells you whats up with the fans. Breadboarding on the bench has produced satisfactory results so now I've designed a pcb and am busy ordering components. The board and fan work off 12V which I get from a 48-12volt buck converter (Mean Well model PSD-15C-12) connected to the Li-ion battery via an inline fuse.

Putting the fans, power supply and pcbs into 40x100 trunking should work nicely.

Next level would be to add a microcontroller and display all fan speeds on a small OLED. Or would that be going to far?

Mind you with that in place you could easily add a bluetooth link to a phone app to display fan status... or even link it into the Sunsynk wifi dongle to show fan status as part of the Sunsynk online app. Now that could be useful.

PS: here is the schematic for the fanspeed monitor.

and a rendition of the pcb

Edited August 13, 20241 yr by Mach4
Add image

On 2023/09/11 at 5:17 PM, slipx said:

Hi. I'm running ESPHome with the config below.

substitutions:
  device_name: sunsynk-fan-controller
  friendly_name: "sunsynk fan-controller"
  device_description: "Fan with speed control"
  temperature_threshold_low: "22" # At what temperature, in celcius, should the fan turn on to its minimum speed
  temperature_threshold_high: "45" # At what temperature, in celcius, should the fan turn on to its maximum speed
  minimum_fan_speed: "25" # What is the minimum fan speed, as a percentage


esphome:
  name: '${device_name}'
  comment: '${device_description}'
  platform: ESP8266
  board: d1_mini

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: ""


wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: '${device_name}'
    password: !secret fallback_password

  fast_connect: true
  power_save_mode: none

    
captive_portal:

ota:
  safe_mode: true
  reboot_timeout: 10min
  num_attempts: 5


# PWM output for the fan speed control
output:
  - platform: esp8266_pwm
    pin: D0
    frequency: 22000 Hz
    id: pwm_output

sensor:
  - platform: homeassistant
    name: "ACTemp"
    entity_id: sensor.sunsynk_radiator_temperature
    id: temperature_sensor
    on_value:
      then:
        - script.execute: set_fan_state
          
# The actual fan entity presented to Home Assistant
fan:
  - platform: speed
    output: pwm_output
    name: "${device_description}"
    id: "the_fan"
 #   on_turn_on:
 #   - switch.turn_on: fan_relay
 #   on_turn_off:
 #   - switch.turn_off: fan_relay


script:
  - id: set_fan_state
    then:
      - if:
          condition:
            lambda: |-
              return id(temperature_sensor).state < id(${temperature_threshold_low});
          then:
            - fan.turn_off: the_fan
          else:
            - fan.turn_on:
                id: the_fan
                speed: !lambda |-
                  if (id(temperature_sensor).state >= id(${temperature_threshold_high})) {
                    // Over upper threshold, fan speed at maximum
                    ESP_LOGD("Fan speed calc", "Temperature is above or equal to upper threshold so setting to max");
                    return 100;
                  }
                  else {
                    float calc_speed = ((100-id(${minimum_fan_speed})) / (id(${temperature_threshold_high})-id(${temperature_threshold_low})))*(id(temperature_sensor).state-id(${temperature_threshold_low}))+id(${minimum_fan_speed});
                    ESP_LOGD("Fan speed calc", "calculated speed = %f", calc_speed);
                    return calc_speed;
                  }

 

Can you show how wiring and power the fans (type of fans and voltage) because mines they does not work with pwm.

 

Thanks