Dave is geeking out

Cooling the Electric Motor Controller

I've got some more bits for the cooling system for the electric motor controller. I did a short video a while ago on what I had then.

Now I have got two temperature probes and displays (they are designed as add-ons for motorbikes). One will be in the pipe coming out of the motor controller cooler plate (to see how hot it heats the water). The other will be just before the pump (to see how much cooler the water is after going through the radiator). I have three rotary switches to control the pump, the radiator fans and the extractor fan. Only manual adjustment initially until we can see how the fans and pump interact best.

Battery Monitoring

Altogether, we have 12 Lithium batteries (LiFePO4) and not all of them have remote temperature monitoring. So I've got three ESP32 microcontrollers and (so far) 10 one wire temperature probes.

Theoretically, I should be able to connect all the probes to one microcontroller, but I think it will be easier to manage one controller per battery bank. This should only require configuration (no programming) using ESPHome which is integrated into Home Assistant (all free software). I can then automate control of fans, send warnings, switch devices off etc It should work out at about £20 per battery bank, which I think makes it great value.

DC Power

I've installed some neat little "black boxes" so that I can run more of our daily infrastructure from DC (much more efficient than having to run the big Inverter to change the 48V DC to 240V AC and then use a "brick" to come back down to 12V or 5V).

So my Raspberry Pi running Home Assistant now gets it's 5V 5A power from the 12V battery. The WiFi Router also gets it's 5V 3A power from the 12V battery. As I mentioned in the Weekly Newsletter the fridge is now running with automated temperature control from the 12V battery.

All the ESP32 microcontrollers and the entire motor cooling system will run from 12V as well. Soon we will be able to turn off the inverter (which uses some power on idle) for hours at a time.

Free Cooking

We have had our Refleks diesel stove on this evening (wow the boat is so cozy with it, not a lot of fine control yet but warmer than we have been the last 7 winters). So I cooked dinner (a chickpea, and veg curry) on it, for free. Delicious 😄

Loving it :-)