Quote Originally Posted by Geoff View Post
If your machine ever stops printing or jams, pull the plug from the wall ASAP or hit the physical power switch. If the machine has failed and leaves the extruder on and for some reason doesnt run the fan, it will overheat the extruder. You wont hurt the machine even if you turn it off while its printing.
The machine had stopped with an error message in the panel, the infamous 0040, was flashing its internal light, and "beeping". I assumed that it knew what it was diong, but I'm glad to know I can power down safely in any future emergencies, thanks!

Here's the full story, with pictures: http://owenransen.blogspot.it/