Octopi dies after Ender 3 power off

Hi, When I turn off my Ender 3 where I have my Octopi connected with a sepret PSU I cannot connect to the webinterface of the Octopi. I need to reboot it and all is ok until I turn off the Ender. Hope someone can help with this?

The expected power-on behavior:

  1. Turn on the printer itself by toggling its power switch ON
  2. Turn on the Raspberry Pi by plugging it in or toggling, say, some switch for this ON

The expected power-off behavior:

  1. Within the OctoPrint interface, choose System -> Shutdown
  2. Wait for the green activity LED on the Pi to stop flashing to let you know that it's fully shutdown in the operating system
  3. Turn off the Raspberry Pi by unplugging its power adapter or toggling a switch to OFF
  4. Turn off the printer by turning its switch OFF

What you seem to be doing is removing power from the printer. The Pi then will try to back-power the printer's control board via the 5V line in that serial cable. It's likely that it then goes into under-power mode so badly that it toggles off power to its network adapters. You'd then lose your remote browser's connection to the Pi.

I have taped the 5V on the USB, so it not powering the printer's control board. I would like to have my Pi running (alway on).. Is that not possible?

That's not prohibited. There are some arrangements where it's just a problem, that's all.

You might try physically disconnecting the USB cable between the two (Pi/printer) to see if that changes things for you.

There are probably many fix attempts at auto-connecting after either power or cable connection loss. The TPLinkSmartPlug includes an auto-connect checkbox. The usb-autoconnect plugin probably does just this. My own VCC Control project is an over-complicated attempt. My earlier USBControl plugin was another effort.


Your scenario (always on) is one I'm using too, with no issues on my end. So it's possible...

Witch Raspberry Pi are you using? 3 or 4?

Pi3B+ and I don't tape / disconnect printer board. it keeps on running of pi power, but without 24V line for motors, hotend or bed