Power off at startup
Hello,
It's been a few days that I have a problem on my I3 MK3S printer with MMU2S.When launching a print, the printer cuts off directly and sometimes asks me if I want to resume printing as if there had been a power outage.
The printer is usually connected to Octoprint, so I unplugged and tried files via the SD card but I have the same problem. I re-installed the firmware, tried a reset, did some self-tests which are good...I heated the nozzle and the plate for several minutes without problems...
Has anyone ever had this problem? Or any idea where it could come from?
Thanks
RE: Power off at startup
What does mean 'cuts off' - reset, power outage or...?
Can you pls. share the error message screen?
Did you do any modification prior to wrong functioning?
What FW version do you have installed?
Pls provide as much as possible information.
even an old man can learn new things 🙂
Standard I3 mk3s, MMU2S, Prusa Enclosure, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI+ Prusalink + Prusa Connect
RE: Power off at startup
You can see the problem on the attached video.
https://share.icloud.com/photos/018CiG-IGCqSB4F98g_Cw_E1A
The only modification I made (apart from adding the MMU) is to have detached the screen and set it aside.
The FW is : 3.11.0
Since I wrote I kept looking and tried something. I removed the power panic cable from the motherboard. This "solved" the clipping problem.
Following this I managed to print two objects of about 40 minutes. And the third print failed.
I now have a new message that appears after about 10 minutes of printing: "THERMAL RUNAWAY"
Following which, I carried out a "self-test" which failed, I had a message telling me to check "heating / thermistor not connected".
After the failure of the self-test, I turned off / on the printer and redid a self-test which succeeded...But when I start printing I always have the message "Thermal Runaway" which appears after a few minutes of printing.
RE:
this trouble started after you installed the MMU or after you detached the display?
Thermal runayway of the bed or hotend?
even an old man can learn new things 🙂
Standard I3 mk3s, MMU2S, Prusa Enclosure, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI+ Prusalink + Prusa Connect
RE: Power off at startup
The MMU has been installed for a long time and I have been able to print many hours without problems.
The trouble appeared suddenly, without modifications or changes, updates...I didn't use the printer for about 3 weeks and when I wanted to print that's I started having problems...
The message is that of the photo
I measured with a multimeter the following measurements:
Thermistors :
hot end ->99.5 kΩ
bed -> 99.3 kΩ
Resistance:
Hot end : 13.7 Ω
Heat bed: 3 Ω
in the room it was about 20°c
RE:
Hi Tom,
was it a one time shot, or repeating issue?
Thermal runaway could happen after the bed or hotend is reaching the target temperature in th moment when your printer is not able to keep the target temperature for a certain time within the temperature threshold. I gues it is +- 5°C. It could happen when during print some thermal shock is comming (open door, start of extruder fan etc. )
The thermistor issue can also happen, when the thermistor wire is partially broken and during the head move it gets a indefinite resistance.
The most important information to get are the temerature values at the moment the error appeares. Can you share this picture?
At the moment of this error the printer stops the heating functions, so the later picture /like you shared) does not give the right information.
Did you encounter any large temperature (hotend or bed) fluctuation?
even an old man can learn new things 🙂
Standard I3 mk3s, MMU2S, Prusa Enclosure, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI+ Prusalink + Prusa Connect
RE: Power off at startup
It's a really weird problem.In my last message, I left the printer turned off and unplugged for 2 days. When I plugged the printer back in, I managed to print a part (about 40 min without problems). Then the next day, I wanted to re-print and it didn't work again...
By looking precisely at the screen, it is the temperature of the hottend which goes down...(The printer is in an enclosure)
Movie : https://share.icloud.com/photos/0bbGoUwVQ5M5gFxv0MPUaiLLQ