mmWave sensor

[lunar cobalt]

Just a quick sensor I made using 5V power supply + ESP32-S3 Super mini + LD2410. Works great!

[runic matrix]

what psu did you use?

[lunar cobalt]

HLK-2M05

[lunar solstice]

I would recommend to add a fuse to your design!

[lunar cobalt]

Where should it go?

[cold badge]

AC Side would be more practical.

[lunar cobalt]

umm so the breakers in the AC panel are not enough?

[cold badge]

What if none are present?,
Would anyone should risk it all ?

[lunar cobalt]

Sorry I didn’t get it! The breakers would just trigger and cut electricity. What risks do you mean?

[cold badge]

I personally wont risk a setup for a breaker not working kind of scenario, to be very honest 🙏
An extra fuse wont cost a huge expense. Better to have one, than to regret later.

[lunar cobalt]

Got it, makes sense. I just wanted to understand it. Should I put one on each AC input or just one on any of them?

[cold badge]

Putting one on +ve is enough,
Should be safe on -ve too as you just need to break the damn failing circuit.
On a unforeseen occurrence, one should be double sure to evade a fire hazard 🙏
That was my only intention.

[lunar solstice]

Would also add a varistor

[lunar cobalt]

So the fuse is on the DC side then? (As you are mentionioning + and -)

[normal cove]

The breaker is last resort. You want a fuse that's closer to the current usage of your device. It would go on the incoming AC line.

[lunar cobalt]

got it, will research that. Thanks a lot everyone!

[lunar solstice]

input side, strongly recommend placing everything soldering pcb. So you can add the fuse and the varistor correctly nicely clean. reason for doing that there if you have a too high current on input that maybe uses 10A only your breaker will not pop but can heatup you device such away you create nasty situations.

Quit possible your supply has a shorting protection already buildin, however good pratice to add it there too an fuse.

anyway don't play with 230VAC if you are clueless on the dangers and discuss with someone around how understands it

I actually really like you 3d printed case, nice job !

[lunar cobalt]

the case is here if you want to look at it https://cad.onshape.com/documents/f9ddee90ad5970b8badde79a/w/28101fc08e0e81b154adbfad/e/ae1becaa878a5f5fc8cd6ba7?renderMode=0&uiState=654930d444e0a06f0dd7e378

[night leaf]

Curious why you're not using a typical and UL listed 😉 USB PSU and then just running that cord out since your MCU visibly has a USB-C and will then supply 5V (or 3V in your case) for the radar module...

could make the case much much smaller then too

[lunar cobalt]

Ah yeah it’s because in mounting them in the ceiling and I have easy access to AC power there

[night leaf]

Just a quick search, and a thought... but could you not use something like this for a more code/safe approach?

Then inside the case you don't need any power supply, just a simple USB cable, low voltage