I have my machine on a rolling cart that has an outlet attached to it. One of the outlets is hot all the time and that is where I plug my machine in. The other outlet is switched and that is where I have my LED's power supply. I ALWAYS, and I mean always unplug my machine after I'm finished carving. Not that this has anything to do with removing the card while the machine is still on but does help me from doing this. Just my 2¢ worth.