CR-6 SE Warning - Dangerous USB! Measure before pluggin in!
If you have a CR-6 SE, you may want to check the voltage between the shell of the USB port and the case of your printer. I am measuring -15V and higher! This is a fire hazard and will damage your computer’s USB port.
When I got my CR-6 SE this month, the USB was working fine. Then, one day when I tried to plugin the USB cable from my raspberry pi to the printer, I see a spark! I immediately pulled out my multimeter to check and guess what the voltage between the shell of the USB, which is supposedly grounded, was measuring -15.8V in relation to the case of the printer! Fortunately, my raspberru pi survived the ordeal because the USB cable was not yet fully plugged in. I measured sevceral more times and now it always shows somewhere between -15.8 and -24V!
I have sent a tech support request to Creality and am still awaiting for their response. I have also posted it on the Creality3d facebook site to warn any other fellow users: https://www.facebook.com/100000048190657/videos/3715236125154624/