MMU2 reset during single color print
Twice now on a long single color print (10 hours+) I have come come back to find the printer still printing just fine, but the MMU2 flashing all 5 lights red. Since there is no filament change needed and the MMU2 is simply disengaged, it doesn't really affect the print. It's still a pain, however, as at the end of the print there is no good way to unload the filament. Since the MMU2 is dead, and can't even be reset because the finda is triggered, I have to manually extract the filament, often by removing the orange Bowden.
Any clue what causes this? I would blame a power glitch (mk3 survives due to power-panic; mmu2 resets, sees filament in finda, starts flashing), but I'm on a UPS that hasn't triggered.
I'm wondering if there is a "MMU2 hasn't received a command in 500 minutes, reset" thing going in the firmware.
This is with the original firmware, I haven't flashed 1.1 yet.
Re: MMU2 reset during single color print
1) Flash the new firmware. It does handle hang ups a bit better.
2) That's running the same g-code, sometimes it works, sometimes not?
I've sen the whole printer reset for no reason, but not what you're describing. If I had to hazard a guess:
I think the retraction at the end of a print is a "hardware" retract - using different settings than your careful tuning. These can be too aggressive, stripping filament and "giving up" after trying to unload.
(Are you the guy using the temperature drop script? Perhaps it's cooling too much before the retract)
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Re: MMU2 reset during single color print
1) Flash the new firmware. It does handle hang ups a bit better.
On my plan. MMU2 is apart right now for new filament feed, so it'll likely be a week.
2) That's running the same g-code, sometimes it works, sometimes not?
Nope, I'm iterating on my filament feed base, so different gcode each time.
I've sen the whole printer reset for no reason, but not what you're describing. If I had to hazard a guess:
I think the retraction at the end of a print is a "hardware" retract - using different settings than your careful tuning. These can be too aggressive, stripping filament and "giving up" after trying to unload.
(Are you the guy using the temperature drop script? Perhaps it's cooling too much before the retract)
In my case, the print is still running just fine, so hopefully the MMU2 never tried to retract (it shouldn't have, 8 hours into a 10 hour single color print on filament1). Also, because it is a single color print I didn't do the ram cooling (yes, that is me, and I agree dropping too low could freeze the filament head in the nozzle. Just not happening here).