Pins to connect for 5v for RPi 3 on Mini RAMBO?  

RE: Pins to connect for 5v for RPi 3 on Mini RAMBO?

Be aware that the Raspberry Pi 3 normaly needs a power supply 5V with at least 2A current. I am not sure, that you will find pins on the board being cappable to deliver that current. I have 3 printers running - all connected to their own Pi´s - every Pi has it´s own power supply. These power supply are not so expensive.

Best regards, Clemens

RE: Pins to connect for 5v for RPi 3 on Mini RAMBO?

Posted by: @jon-b

I've upgraded my MK2 to a MK2.5S and would like to provide power to my octopi (Pi3) from the Board. I've seen various pin outs, but the ones I see don't seem to match my board. Is it possible or do I need to go the buck convertor route? TIA

For the Pi3B/B+ or Pi4 i would prefer to use a 5.1V 2.5A powersupply to avoid voltage instabilities. An external power supply 5V / 3A e.g. the Meanwell RS-15-5 does not cost much and can be easily integrated into a case: Meanwell RS-15-5

For the Pi4 maybe this: Meanwell RS-25-5

RE: Pins to connect for 5v for RPi 3 on Mini RAMBO?

FWIW On the OctoPrint board, all to frequently "strange" errors are tracked down to PSU issues. I don't know if it's relevant but I note that the official PSU for Pi 3 is listed as 5.1V.

Are you sure the PSU on your printer has 2.5A headroom, perhaps the straw ....

Good advice from kart-herbert, go the extra mile and be sure.

RE: Pins to connect for 5v for RPi 3 on Mini RAMBO?

I have adjusted the Meanwell (PS-15-5) power supply to 5.1 volts and using the Pi3B + with absolutely no errors for over 2 years. I highly recommend it.

My Pi3B+ -> no undervoltages:

If the voltage on the Pi is too low or unstable. Informative links:

https://www.element14.com/community/thread/64029/l/under-voltage-detection-raspberry-pi-3-b?displayFullThread=true

https://www.scivision.dev/raspberry-pi-power-stability/

https://elinux.org/RPi_Hardware