3D Printing - Ender 3 Pro USB powering problem

The  problem arise when the Ender 3 Pro is connected to a computer via USB.

The connection between the two is via USB and the connection bring also the power (+5V).

In my case the computer is a Raspberry Pi 4 running OctoPrint.


When the OctoPrint is running, i.e. when the Raspberry Pi is On, the USB connection brings also the power and that power is enough to power on the Ender 3 console when the main power of the printer is Off.
Quite annoying.

The solution is to remove physically the power from the USB cable.
There are no options to remove pro-grammatically power from an USB port of the Raspberry.
There are 3 ways to do so :

1. cutting the USB cable power line
2. printing some kind of shield for the USB-A connector
3. manually covering the USB-A power pin with insulation tape

The solution 1 is not elegant and can easily damage other cable connections.
Anyway after that the cable can not be used for anything else

The solution 2 is feasible and is elegant.
I did find two projects on Thingiverse for that :

• USB cable +5v Pin-1 isolator
• USB-A male plug pin isolator (back-power blocker)

However I was unable to obtain a decent print of the object since is just about 1 layer and probably the printer is not yet set decently.
After two or three attempt I decided for the method 3.

I did cut a small piece of insulation tape, large enough to cover the power pin and long enough to come out over the USB-A connector.
Voila', no power anymore to the printer. from the Raspberry Pi.
Now the console turn on only when the main power supply of the printer is On.

Be sure to check that OctoPrint (or whatever you use) can still connect with the printer.

Here few pictures to illustrate the process, more difficult to say than do.

The USB-A connector. The +5V is on the right

Placing a piece of tape over the +5V strip

Be sure to have it long enough to come out and go on the front and ...

... on the back. In this way the tape is not removed when inserting the plug.