I wanted a way to monitor the temperature of our MultiPlus-II 48V 5000VA. Since we can’t retrieve the internal temperature of the device,I was thinking of attaching a DS18B20 to its toroidal transformer. Stick the temperature sensor with Kapton tape and have an ESP32 read the value which would adjust an external fan that would helps blow cooler air in.
Is there something I should know before I do this? Would it be better to just place it somewhere else inside or perhaps just monitor the air inside the MultiPlus-II?
The outcoming air can very easily be measured with a ready to use thermostat, like the STC-1000, it can heat and cool, and there are 12V, 24V and 230V models of it and have a good visible display.
Also, if your techroom is noisy, sometimes you cannot hear the fan(s), so we place a tell-tale, a very lightweight piece of fabric to indicate airflow.
The inverter internals fan(s) are normally fully on at 40 degrees C.
To power the fans we use often a Desktop home computer power supply, the green wire (normally) is the switch on/off of the power (to a black one), it has plenty of power to supply many 12V fans.
You could also use the temperature sensor supplied with the MP2 and then control it if necessary. At the very least, you could use it quite easily for taking readings and visualising the results. That would show whether it’s worth building a complicated circuit here.
For example, I run a normal “desk fan” via a smart plug and use it to blow air over the MP2.
What I’m getting at is that perhaps the effort simply isn’t worth it. Unless you want to tinker, of course.
