EZBlocker Power Blocking USB Cable

How the Power Blocker Works

The power blocker just severs the 5V connection from the printer board to the USB port. The printer power supply must be ON when using it with USB since power is not being delivered to the printer board from the USB port anymore. All of our power blockers are tested on a printer before they are sent out. 

Troubleshooting Connections

If you are having issues with the Power Blocker you can try these troubleshooting steps to isolate if you have an issue with the board and/or your USB cable. Your printer power supply must be ON and the printer plugged in to AC power.

1. Plug the printer into your computer and make sure you can establish a connection from the computer to the printer over the USB port. You must have the correct COM port and baud rate set
   1. If you cannot connect over USB to the printer then the issue lies with either your printer board or the USB cable. Try another USB cable that you know works and is a DATA cable (some USB cables are power only and these will not work)
2. Once you can connect to the printer over USB, install the power blocker and try again. If your USB cable and printer board are working, then you will be able to connect to the printer COM port over USB.

Octoprint Connection

When you have the printer connected to Octoprint, you should be specifying the COM port and not relying on the “AUTO” setting. The “AUTO” setting does not work reliably all the time. You should also do a full reboot on the Pi system if you are having issues connecting to your printer.