MK3 / Einsy Chassis Ground
Our MK3 was freezing then resetting itself on every print, but always in a different file location. We grounded Einsy to the printer frame, making a chassis ground, and now all is well.
See thread original-prusa-i3-mk3-f30/mk3-resets-while-printing-t14657.
Re: MK3 / Einsy Chassis Ground
A new thread is now reporting the same problem, along with a successful application of essentially the same fix:
https://shop.prusa3d.com/forum/original-prusa-i3-mk3-f30/random-resets-earthing-problem-easy-fix--t14986.html
The original thread had three people reporting this problem. One more has now reported a successful fix:
https://shop.prusa3d.com/forum/original-prusa-i3-mk3-f30/mk3-resets-while-printing-t14657-s10.html#p71963
The same poster also previously had a PSU fail "in a very common way" and noted:
After following the PSU failure thread it seems to show that that the Prusa PSU fails almost exclusively in the US on 120V ac.
Passing on a speculation from my local expert: Maybe the system, operating with greater power reserves under European 220V, is less sensitive to noise; but operating closer to its limits under US 120V, is more sensitive to noise. Has to work harder to maintain power regulation. Our printer is sitting on a plastic table on a concrete floor. If it was a metal table would we still have seen the resets? Possibly not.