My Sunsynk 8kw silence hack

[slipx]

Just an update. Added a Wemos D1 Mini to control the fans. Running at 100% all the time is not efficient. The fan speed is automatically regulated based on the AC temperature and the set temperature threshold.  It's a lot quieter now. 

 

Edited March 28, 2023 by slipx

[branderplank]

On 2023/02/27 at 5:15 PM, BrettB said:

Hi Everyone,

Thought I'd share this because I have noticed a few people concerned or frustrated with the fan noise from the 8kw Sunsynk inverter. I couldn't install my inverter in the garage because I do a lot of woodwork in there and I know the dust would cause issues in the fans and heatsinks. So its mounted at the end of our passage where it meets with the garage through the door. The noise at night was really an issue for me. During load shedding the fans would usually kick in. Specially when the aircons where running. This is obviously when the inverter was doing a lot of work and required cooling. Then also after load shedding when the batteries were charging the fans would come on intermittently. Bloody irritating when trying to sleep.

The following pics is what I came up with. 5 decent quality 92mm PC fans on the vent side to constantly pull air through. Now these fans don't have the CFM or static pressure rating of the built in fans. But they are dead quite and they keep a constant steady flow of air over the heatsinks. On average, they keep the inverter 10-15 degrees cooler according to solar assistant. I have only had them in for 5 days now and the temperature has never gone over 55 degrees which is the trigger point for the built in fans. I ran all 4 aircons plus the air fryer for 30 mins and the inverter got up to 49 degrees. But when idle, it sits at 35-40 degrees. I am still waiting for a full sun day with load shedding where the MPPT's and the inverter are under a decent constant load to see what happens. Today the MPPT's where hitting around 8kw peaks while charging, and about 4kw on the inverter and it never went over 41 degrees.

I have mounted the fans about 10mm of the exit vent so none of the holes get blocked. The idea is that when the internal fans kick in, that air can just blow through my external fans. For now, I have just hot glued the fans to the wall and hot glued a piece of trunking cover to side(proper life hack style =D). I am busy designing a decent 3D printed bracket to hold all 5 fans and clips onto the vent hole at 4 points. No alterations have been done to the inverter at all so no future warranty issues. The fans run off an external 12v supply. I have wired it through a sonoff switch with the idea to control them through home assistant based on inverter load and temps.

 

Very nice - been looking at something like this.

For the wiring I assume you took off the 4 pin connectors and did some extending and crimping?

[AndrewGoldy]

I see some are using plastic and 3D printed parts. I stuck with wood ... for the moment! 

[sAnD.mAn]

How are you guys mounting the 3d printed cover to the inverter?

[Modina]

On 2023/03/14 at 7:22 PM, BritishRacingGreen said:

In theory, if you use 4 identical fans and each fan is under exact same mechanical load, you would drop more or less 12v over each. But in practise the input reisstance of each fan motor vary, and if any fan experience more mechanical load than the others, that effective input resistance will drop, causing disturbance in the voltage sharing. 

You could run the 4 fan motors in series if you place a 12V zener diode across each one.  Then add a resistor or perhaps a LM317 to drop the 8 or so volts that the batteries are over 48V.  The fans shown are rated at 120mA each.  So I would use the LM317 (TO220 case) as a constant current regulator set to about 130 or 140mA.  To be on the safe side, use 1W rated zener diodes.  Use a 9.1 ohm  1/2W resistor to "program" the LM317 for a 137mA constant current.

[Modina]

On 2023/03/14 at 7:22 PM, BritishRacingGreen said:

In theory, if you use 4 identical fans and each fan is under exact same mechanical load, you would drop more or less 12v over each. But in practise the input reisstance of each fan motor vary, and if any fan experience more mechanical load than the others, that effective input resistance will drop, causing disturbance in the voltage sharing. 

You could run the 4 fan motors in series if you place a 12V zener diode across each one.  Then add a resistor or perhaps a LM317 to drop the 8 or so volts that the batteries are over 48V.  The fans shown are rated at 120mA each.  So I would use the LM317 (TO220 case) as a constant current regulator set to about 130 or 140mA.  To be on the safe side, use 1W rated zener diodes.  Use a 9.1 ohm  1/2W resistor to "program" the LM317 for a 137mA constant current.

[Modina]

Sorry about the double posting.  Somehow the message got stuck the first time. 

[slipx]

14 hours ago, sAnD.mAn said:

How are you guys mounting the 3d printed cover to the inverter?

Printed some brackets to attach to the wall

[FuzzyBullets]

Here is temperature speed controller for 4 pin pwm fans.

https://www.banggood.com/ZHIYU-DC-12V-24V-48V-2-Way-Cooling-PWM-4-Wire-Fan-Temperature-Controller-Temperature-Speed-Display-p-1162516.html?rmmds=myorder&cur_warehouse=CN

Will be doing the install when fans arrive. This controller can handle up to 3Amp. Will run your 4 fans.

 

[Speedster]

On 2023/02/27 at 5:15 PM, BrettB said:

Hi Everyone,

Thought I'd share this because I have noticed a few people concerned or frustrated with the fan noise from the 8kw Sunsynk inverter. I couldn't install my inverter in the garage because I do a lot of woodwork in there and I know the dust would cause issues in the fans and heatsinks. So its mounted at the end of our passage where it meets with the garage through the door. The noise at night was really an issue for me. During load shedding the fans would usually kick in. Specially when the aircons where running. This is obviously when the inverter was doing a lot of work and required cooling. Then also after load shedding when the batteries were charging the fans would come on intermittently. Bloody irritating when trying to sleep.

The following pics is what I came up with. 5 decent quality 92mm PC fans on the vent side to constantly pull air through. Now these fans don't have the CFM or static pressure rating of the built in fans. But they are dead quite and they keep a constant steady flow of air over the heatsinks. On average, they keep the inverter 10-15 degrees cooler according to solar assistant. I have only had them in for 5 days now and the temperature has never gone over 55 degrees which is the trigger point for the built in fans. I ran all 4 aircons plus the air fryer for 30 mins and the inverter got up to 49 degrees. But when idle, it sits at 35-40 degrees. I am still waiting for a full sun day with load shedding where the MPPT's and the inverter are under a decent constant load to see what happens. Today the MPPT's where hitting around 8kw peaks while charging, and about 4kw on the inverter and it never went over 41 degrees.

I have mounted the fans about 10mm of the exit vent so none of the holes get blocked. The idea is that when the internal fans kick in, that air can just blow through my external fans. For now, I have just hot glued the fans to the wall and hot glued a piece of trunking cover to side(proper life hack style =D). I am busy designing a decent 3D printed bracket to hold all 5 fans and clips onto the vent hole at 4 points. No alterations have been done to the inverter at all so no future warranty issues. The fans run off an external 12v supply. I have wired it through a sonoff switch with the idea to control them through home assistant based on inverter load and temps.

 

Did you perhaps ever get around to designing a 3d-print bracket?

 

Also, have you considered powering it straight from the 12vdc output on the inverter?

[anthonyhugo]

Ho guys, the way I "attached" it to my inverter was to print these 2 brackets and glue them to the fan enclosure (using my wife's nail glue haha)

 

https://www.thingiverse.com/thing:6058451

 

Then on top of these 2 brackets I just put a scuba diving weight, it creates a cradle of sorts to put the weight, then this just sits on top of the inverter...

 

Please don't judge my rudementary 3D design skills too harshly lol, I'm very noob at this

 

(apologies don't have photo will try get one)

 

Cheers

Ant

Edited June 2, 2023 by anthonyhugo

[ZS1SCI]

Heya, thanks for everyone's feedback on this matter

This modification should be part of the standard design.

I took the cheap and fast way, butyl tape and cable ties and a spare 12V PSU

Running at 11V to extend the lifespan of the fans with some pending cable management.

Works pretty darn well.

 

Huzzah

Edited August 5, 2023 by ZS1SCI
30day chart one week later

[Jeff-dandare100]

Hello guys.

I have what probably seems like a doff question. 

Should the extra 4 fans of this mod on the side be switched on and left on (resulting in the inverter running very cool) or be controlled by the internal temperature and turned on when needed ?

The reason I ask is :

Does the constant cooling and heating affect the inverter at all ? ie Does the temp change of around 15 degrees up and down (many times a day) cause the components in the inverter, on the heatsink with thermal paste, to degrade, crack or move ?

Or am I living in the dark ages and worrying about nothing ?

Shot

Jeff

 

Edited August 17, 2023 by Jeff-dandare100

[Buyeye]

1 hour ago, Jeff-dandare100 said:

Hello guys.

I have what probably seems like a doff question. 

Should the extra 4 fans of this mod on the side be switched on and left on (resulting in the inverter running very cool) or be controlled by the internal temperature and turned on when needed ?

The reason I ask is :

Does the constant cooling and heating affect the inverter at all ? ie Does the temp change of around 15 degrees up and down cause the components in the inverter, on the heatsink with thermal paste, to degrade, crack or move ?

Or am I living in the dark ages and worrying about nothing ?

Shot

Jeff

 

I think that it would be impossible for this setup to cool the inverter lower than ambient temperature so it could never harm only improve cooling to ambient temperatures. 

[ZS1SCI]

On 2023/08/17 at 11:33 AM, Jeff-dandare100 said:

Hello guys.

I have what probably seems like a doff question. 

Should the extra 4 fans of this mod on the side be switched on and left on (resulting in the inverter running very cool) or be controlled by the internal temperature and turned on when needed ?

The reason I ask is :

Does the constant cooling and heating affect the inverter at all ? ie Does the temp change of around 15 degrees up and down (many times a day) cause the components in the inverter, on the heatsink with thermal paste, to degrade, crack or move ?

Or am I living in the dark ages and worrying about nothing ?

Shot

Jeff

 

I have mine running the 4 fans at 11V permanently, the lower voltage is so that the fans run at a lower RPM, therefore theoretically extending their lifespan.

You can lower the voltage with two resistors R1=470Ω and R2=5.6kΩ connected like this:

from a normal 12 1A DC adapter to about 11V. [ref]

Replacements should be cheap if one fan goes.

23 hours ago, Buyeye said:

I think that it would be impossible for this setup to cool the inverter lower than ambient temperature so it could never harm only improve cooling to ambient temperatures. 

Also agreeing here, electronic components favour cooler conditions.

Cheers

[Jeff-dandare100]

On 2023/08/18 at 12:17 PM, ZS1SCI said:

I have mine running the 4 fans at 11V permanently, the lower voltage is so that the fans run at a lower RPM, therefore theoretically extending their lifespan.

You can lower the voltage with two resistors R1=470Ω and R2=5.6kΩ connected like this:

from a normal 12 1A DC adapter to about 11V. [ref]

Replacements should be cheap if one fan goes.

Also agreeing here, electronic components favour cooler conditions.

Cheers

 

On 2023/08/17 at 12:51 PM, Buyeye said:

I think that it would be impossible for this setup to cool the inverter lower than ambient temperature so it could never harm only improve cooling to ambient temperatures. 

 

 

Thank you for the insight and links guys.

 

[Carl Anthony]

On 2023/03/07 at 7:08 PM, slipx said:

@BrettB thanks for the inspiration. Here is my attempt at a 3D printable fan holder. Settled on 4 fans as the vents are not that big. Still need to mount this to my wall. I used the Cooler Master Sickleflow 92 fans.

https://www.thingiverse.com/thing:5896902

@slipx did you print the brackets yourself or did you have someone print them for you?

Looking to do this for both 5kW SS...the master has 8 x panels connected to it and temp gets up to 64+ fan runs for quite long these days.
System was installed end of May and only had the fan run once in that 1st week or 2 and thereafter it was winter.
Now that its warming up seeing the temp on the master constantly be in this range and fans normal kick in after 58.

[slipx]

Hi. I printed myself. For the 5Kw I think that the fans get mounted underneath so you might need a different bracket.

[Jeff-dandare100]

Here is what I ended up doing : It is working very well, thank you for the idea.

 

Roll on summer

 

[WAP]

This is mine. Just took a piece of alu flat bar and bent the one end 90 degrees and bolted the other end at the fan side to the 3d printed fad mod. So it just hooks over the inverter.

 

B

Both temps dropped by between 10-15 degrees. My ambient temp in the garage never goes above 15 degrees.

[WAP]

Average Temps for May 2023:

Average Temps for June 2023:

 

Edit: I installed the fan mod during May 2023.

Edited August 24, 2023 by WAP

[Carl Anthony]

Ok guys...I may have ordered a slight bigger fan that I thought...120mm...size does matter?

 

So I have just test fitted them - they are both laying direct on the inverter...with just the one fan on the left slight hum...with both definitely noticeable.

Which is a problem because the system is in the study, where I work daily...so need to figure how to mount them so they like 1cm from the inverter.

Just running them for 30min like this 10 degree drop in temp between 17:00 - 17:30...true test will be midday tomorrow when PV is BOOSTING.

 

I could maybe get away with just having 1 fan per inverter instead of 2...will see how it goes with testing over the next few days...

Edited September 9, 2023 by Carl Anthony

[Carl Anthony]

Yesterday @11:52 vs today @ 11:52...today there is 1 x external fan on each inverter. Fans running since 07:34.

[Greglsh]

 

Just an update. Added a Wemos D1 Mini to control the fans. Running at 100% all the time is not efficient. The fan speed is automatically regulated based on the AC temperature and the set temperature threshold.  It's a lot quieter now. 

 

I know it has been a long time but what software did you use on the Wemos D1 mini to control the pwm cable for the speed of the fan.

[slipx]

 

I know it has been a long time but what software did you use on the Wemos D1 mini to control the pwm cable for the speed of the fan.

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;
                  }