DIY ESS - Variable Fan Speed with PWM & Thermistor

This morning, I am experimenting and trying to find a simple solution to make the ESS Fan accelerate when the temperature in the Metal Cabinet is rising and slow down when it is back to an acceptable value

As you already know, the fan is controlled by a PWM kit that I soldered 2 weeks ago and I can adjust its speed using the PWM kit potentiometer; That is already a good step, but I would like to make it better

In the Arduino starter kit I got a year ago, there was a Thermistor and I used it between the negative and the variable output pin of the potentiometer: It looks like it is working, and you can see the pictures and video where I increase or decrease the fan speed using an ice pack and a soldering iron to make the Thermistor resistance change based on the temperature changes

Thermistor temperature

Ice pack temperature

Soldering iron temperature

Cooling the Thermistor after heating it up

Fan speed changes ...

DIY ESS - Soldering of the PWM kit and Using it ... for the Fan Speed Control

Last sunday, I finally took some time to solder the PWM kit I got few weeks ago

A little test with a 12V AGM battery and a small motor

It worked !

But when I tested it instead of the capacitor and resistor on the Tyco Kilovac EV200A1ANA, then I got smoke and blew the 2A fuse on the 24V line ... after hearing the contactor having difficulties to close properly with its usual big clap. There must have been too much consumption from the coil to close I guess and the MOSFET was burning hot !

So I kept the resistor & capacitor Economizer solution for the Kilovac, tested for sevral weeks now, and   used this PWM kit for the fan speed control on the metal cabinet, manual control that is for now

After long tests with the fan at different speeds, nothing was over heating, and it seemed like a good match

So I plugged it on 24V line of the ESS to further test it with the voltage it will get when mounted in line on the switched 24V

24V taken at the source, right after the 2A fuse