diy solar

diy solar

Separate power supply for IoT

jbatx

I make stuff with things
Joined
Jun 8, 2021
Messages
184
Location
Austin, TX
...this seems like a reasonable forum for this post.

I have a few esp32 based devices in my utility container (20' connex).

Three monitor the batteries using serial connection to Overkill bms's.

One monitors water flow and usage and toggles a uv sterilizer.

Right now, the devices are usb powered from the main inverter. The work fine.

The problem I'm trying to solve for is that in the event of an inverter shut off, I want the devices to continue to function.

I want them to run after inverter shut off until the bms's cut discharge.

This is the gap between about 47v and about 42v when one or another cells drops to 2.5 and a bms does a low voltage cutoff. I want to be able to monitor that gap.

Seems like a simple problem to solve and I could probably do it fine on my own. However, I value the brain power and experience of this community.

A 48v to 12v converter is easy enough. Then, I need to go from 12 to 5v or a very stable 3.3. To power the esp32's

What hardware would you use for this?

What would you do?
 
48V -> 12V converters are easy enough to source, I'd just get one of those + a 12V-powered USB outlet.
 
I'm also using DC to DC converter to power Raspberry Pis. In my case I am also using a https://lifepo4wered.com which allows me to use 12V to feed to the Pi and have backup power to the Pi. I'm using 12V so that can use same 12V for other devices. I've also used DC converter to 5V and powered the Pi directly as well which I'd think your ESP32 based devices could use as well.
 
I use these power-while-charge batteries.
Basically plug them in and power USB IOT devices with them. When power fails, IOT device keeps running ( mine lasted a few days in the last power failure).
 
Back
Top