Hi, I have a shared USB hub that can delivery only 17w at max combined for 2 ports.
I’ve been using it only with a pi4 connected and has been working great, but now I need to attach a pi zero 2w to the other port and I’m concerned wether or not the 17w are enough power for both. I can’t really plug an additional power brick in the location where they are, so it 17w is enough, that would really help me.
Does anyone have any metrics?
An option to get a raw power consumption overview is to use an USB power meter and measure the approx. mean power of every device.
This gives a first hint but not a high sophisticated examination of power consumption peaks.
17W should however be sufficient for an RPi 4 + Zero 2 W, as long as you do not have power-intense USB devices attached to the Pi’s. It is below the recommended PSU capacity, but that has some safety margin, of course.
From what I read, it should be ok. The Zero 2W uses only a SD card + ethernet adapter (usb) and the pi4 uses just an attached 3.0 SSD.
I have both connected and they seem to be working fine. None of both are overclocked.
With a dedicated PSU for the SSD?
especially on RPi4, USB ports are not designed to power HDD/SSD. We have seen quite some issues where people did not use external PSU.
And an SSD is what I was referring to with