Bed Thermal Runaway
The nature of heating up the extruder and bed seem to have changed in the latest FW rev for MM printing. The bed heats up independently of the nozzle, and while I don't think it matters per se (though it feels SLOWER OVERALL), I now see that I have a 'Bed Thermal Runaway' message the pops up, sometimes stopping a print, sometimes NOT. I've checked the connections to the bed heater and thermistor and they look fine, but watching the INFO display during the printing of PETG, it really struggles to keep the bed at 90C, so it was lowered to 80 to do a simple print (this was after the print STOPPED with Bed Thermal Runaway and the standard 90C), with this print completed albeit reading Bed Thermal Runaway on the display, when I removed it.
Anybody else seen this happen? I've printed LOADS of PETG, and I have never seen this with the previous SW loads.
Thanks,
Steve
PS Up and running on MM Single Mode, hopefully can get it fully working today : 😎
Re: Bed Thermal Runaway
The bed heats up independently of the nozzle
Purely down to Start GCode settings; easy enough to change.
I now see that I have a 'Bed Thermal Runaway' message the pops up...Anybody else seen this happen?
Yeah, there have been a few reports on the forum. Couple of things to check:
1. Ensure connector if firmly home in RAMBo socket
2. Ensure bed movement doesn't make the connect move.
3. If you r connection and cable management is OK, check the 12V rail and maybe increase it by 0.5V. It should be OK up to 13V or slightly more.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Bed Thermal Runaway
totally agree with Peter.
just want to add another point that made a few times problems during the last weeks:
check that the temperature sensor is attached properly underneath the heatbed, with good thermal contact to the pcb (not just only in a fold of the kapton tape).
some useres reported that it has gone loose... so the printer detected a much lower temperature than there really was and tried to increase the bed current without any success -> bed thermal runaway error.
dem inscheniör is' nix zu schwör...
Re: Bed Thermal Runaway
I do have a similar issue (if not the same). On trying to print ABS the bed heats up to 100°C, the print starts and then ever so slowly the bed temprature constantly drops until it ends in either "Bed thermal runaway" error or the printed piece simply gets loose.
To me it looks like the heat bed temprature is not monitored during printing or at least its control is really too slow to keept the temprature up.
Connectors are okay and so is the sensor mounting on the bed.
Firmware is the latest 3.0.11.
Re: Bed Thermal Runaway
Firmware is the latest 3.0.11.
Latest firmware for MM upgrade is 3.0.12-RC1 from here: http://www.prusa3d.com/drivers/
Are you using the part cooling fan? Have you tested/tweaked the PSU voltage? Are you printing in an enclosure?
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Bed Thermal Runaway
I was using the latest software for MM. Inspected the connectors. Will someday to the power supply trick, saw that elsewhere and thought it made sense to the point of wondering why Prusa didn't do it themselves as part of the kit.
The end fix was applying some gentle pressure on the bed thermistor, and it seems to be keeping better temperature, went straight to 100C, no further issues thus far.
Appreciate all of the advice that has been provided. Now, I just need to figure out how to make consistent multilateral prints. The whole thing has been one issue after another, and not that I don't get a bit of self satisfaction knocking down small issues. It's just that I don't think they should be present in a product that is 6 months over due.
I'm clearly not the only one having filament jams, software issues (with both Slic3r and the post processor), etc, etc.
ARE WE STILL IN A BETA TEST? This isn't directed to you Peter, just frustrated with the whole thing thus far, I didn't think I was buying $300 in frustration, but that's where it is now, and the PRUSA team isn't doing themselves any favors when you send a note to info@ and don't get a timely reply.
Re: Bed Thermal Runaway
Latest firmware for MM upgrade is 3.0.12-RC1
That's for "MK2 Multi Material only for now." to my understanding. I do have a MKS2 with just one extruder. Sorry, I didn't mention that. I was hijacking this thread as I thought the heat bed is the same for both variants.
Are you using the part cooling fan?
I'm using the printer, print and filament settings provided by the install package of Prusa slicer. Just changed the temperatures of bed and extruder to ABS in the filament setting. Whatever is set as default for the fan there (not sure need to look up) I' using
Have you tested/tweaked the PSU voltage?
Tested: no. I was asuming that if it's good enough for heating up in the first pace it should do for the printing as well. But I might be mistaken here. How would I do the tweaking?
Are you printing in an enclosure?
No
Re: Bed Thermal Runaway
That's for "MK2 Multi Material only for now." to my understanding. I do have a MKS2 with just one extruder.
Andreas
Sorry, this is the MutliMaterial area, so if you are posting here, it must be assumed that you hae the MM upgrade.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Bed Thermal Runaway
ARE WE STILL IN A BETA TEST? This isn't directed to you Peter, just frustrated with the whole thing thus far, I didn't think I was buying $300 in frustration, but that's where it is now, and the PRUSA team isn't doing themselves any favors when you send a note to info@ and don't get a timely reply.
Stephen
I am well aware that your comments are not directed at me. Myself and a few others have spent the last 6 months beta-testing, giving up our free time and many rolls of filament so that everyone receiving this upgrade can get it working without too much hassle, so it is very frustrating to become aware of your situation.
As you may gather, I am currently printing without issue, and we have to get you to that position. Let's work on it...
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Bed Thermal Runaway
I know I placed my comment in the wrong section at the first place but now that I started... 😉
Just to let you know that I could solve my issue with the following three changes (might be of interesst for those reading through this thread):
@PJR: thanks, you were asking the exactely right questions to guide me to a solution.
Re: Bed Thermal Runaway
I am not sure if anyone has found a fix yet?
I am having the exact same issue. I have been printing ABS for over a year without any issues. All has been great...
Then a couple days ago - I get a "bed thermal runaway". I try again and notice that the bed is not maintaining 100°. Its struggling to maintain 94. The red led is constant.
I try in PLA 60° bed temp.. No problem, perfect prints. SO - I have checked all the connections, and to the best I can see, all looks well. Everything looks tight. I wiggled the bed wires, and no change. The thermister appears attached (best I can see under there (without taking the bed off) ) seems to be reading the temps correct (checked with IR temp gun).
SO, now what...?
Am I looking at the wires, the power supply, the bed, the thermister. Does anyone have an idea why the bed cannot maintain temp, and what exactly I would check.? The electronics box is a mess, and not exactly easy to mess with while trying to print.
Thanks So much,
Chuck
Re: Bed Thermal Runaway
Hello
i think any bug in front fan. If i change filament settings /cooling (keep fan always on) in inslicker, and do gcode , this gcode give me this message in work.
Profile Prusa ABS
Re: Bed Thermal Runaway
I fixed the problem.
My problem was the thermistor was detached from the bed, because of Y axis movement pulled the thermistor cord continuously, and finally the thermistor was pulled out of thermo tape and was in the air.