Duet mini 5+ freezes and shuts off heaters

Michael Hathaway

@droftarts Hello, I do not have anything plugged into those headers. I am thankful all of you are working hard to help me on this. I was going to wait to share what I have found until I can confirm.

So far I have printed multiple prints which have all failed.

Before I go further, I want to add that I am printing high temperature PA66 CF in the 330C range. I have a custom built E3D copper/titanium air cooled head unit I created with dual fan 10.2cfm heat break cooling. Pt1000/50w cartridge all Slice engineering. Printing at these temperatures is a common daily practice.

After multiple prints failed, I installed a new pt1000. Result: print failed with an "emergency shutdown" listed in console.

Removed SDcard and installed new card with cloned programing. While heating hotend, I received a heat fault due to not heating fast enough. I found this interesting because the identical config was used with no heat fault before, only the sdcard was changed.

Ran M303 H1 S350 tuning, compared the results which changed and added to config.g. For safety measure, I ran for both the hotend and the bed.

For my next print, I changed out spools to lower temperature Nylon which is now at 280°C instead of 330°C.

Ran a small print which was successful. 1st in two weeks of struggling.

I am currently testing more prints at this lower temperature and then I will reload my expensive material back on to test. I have been working day and night and I will keep you updated with what I find.

Michael Hathaway

@phaedrux said in Duet mini 5+ freezes and shuts off heaters:

Static build up maybe? Is the frame grounded? Is the PSU - side grounded to earth?

Yes, all electrically grounded to an earth ground.

Michael Hathaway

Additional fail, just now.

Only this time, the heaters did not shut off. Printer just frozen in place.

9/10/2022, 3:30:58 PM 	m122
=== Diagnostics ===
RepRapFirmware for Duet 3 Mini 5+ version 3.4.1 (2022-06-01 21:06:56) running on Duet 3 Mini5plus Ethernet (standalone mode)
Board ID: 6MFQS-V096U-D65J0-40KMJ-JS03Z-R72JU
Used output buffers: 1 of 40 (40 max)
=== RTOS ===
Static ram: 103684
Dynamic ram: 105420 of which 0 recycled
Never used RAM 32152, free system stack 118 words
Tasks: NETWORK(ready,26.0%,178) ETHERNET(notifyWait,0.2%,562) HEAT(notifyWait,0.0%,326) Move(notifyWait,0.0%,265) CanReceiv(notifyWait,0.0%,942) CanSender(notifyWait,0.0%,348) CanClock(delaying,0.0%,331) TMC(notifyWait,0.7%,71) MAIN(running,72.2%,418) IDLE(ready,0.0%,29) AIN(delaying,0.8%,264), total 100.0%
Owned mutexes:
=== Platform ===
Last reset 06:52:35 ago, cause: software
Last software reset at 2022-09-10 08:38, reason: User, GCodes spinning, available RAM 32752, slot 1
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00000000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
Error status: 0x04
MCU revision 3, ADC conversions started 24756664, completed 24756664, timed out 0, errs 0
Step timer max interval 751
MCU temperature: min 61.7, current 61.9, max 63.2
Supply voltage: min 23.8, current 24.1, max 24.3, under voltage events: 0, over voltage events: 0, power good: yes
Heap OK, handles allocated/used 0/0, heap memory allocated/used/recyclable 0/0/0, gc cycles 0
Events: 0 queued, 0 completed
Driver 0: standstill, SG min 0, read errors 0, write errors 0, ifcnt 41, reads 3363, writes 1, timeouts 0, DMA errors 0, CC errors 0
Driver 1: standstill, SG min 0, read errors 0, write errors 0, ifcnt 37, reads 3363, writes 1, timeouts 0, DMA errors 0, CC errors 0
Driver 2: standstill, SG min 2, read errors 0, write errors 0, ifcnt 41, reads 3364, writes 1, timeouts 0, DMA errors 0, CC errors 0
Driver 3: standstill, SG min 2, read errors 0, write errors 0, ifcnt 27, reads 3363, writes 1, timeouts 0, DMA errors 0, CC errors 0
Driver 4: standstill, SG min 0, read errors 0, write errors 0, ifcnt 19, reads 3364, writes 0, timeouts 0, DMA errors 0, CC errors 0
Driver 5: not present
Driver 6: not present
Date/time: 2022-09-10 15:30:56
Cache data hit count 4294967295
Slowest loop: 5.15ms; fastest: 0.13ms
=== Storage ===
Free file entries: 9
SD card 0 detected, interface speed: 22.5MBytes/sec
SD card longest read time 1.0ms, write time 6.3ms, max retries 0
=== Move ===
DMs created 83, segments created 19, maxWait 0ms, bed compensation in use: mesh, comp offset 0.000
=== MainDDARing ===
Scheduled moves 142236, completed 142236, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== AuxDDARing ===
Scheduled moves 0, completed 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters 0 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
Heater 0 is on, I-accum = 0.4
Heater 1 is on, I-accum = 0.5
=== GCodes ===
Segments left: 0
Movement lock held by null
HTTP is idle in state(s) 0
Telnet is idle in state(s) 0
File is idle in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger is idle in state(s) 0
Queue is idle in state(s) 0
LCD is idle in state(s) 0
SBC is idle in state(s) 0
Daemon is idle in state(s) 0
Aux2 is idle in state(s) 0
Autopause is idle in state(s) 0
Code queue is empty
=== Filament sensors ===
Extruder 0 sensor: ok
=== CAN ===
Messages queued 576, received 0, lost 0, boc 0
Longest wait 0ms for reply type 0, peak Tx sync delay 0, free buffers 18 (min 18), ts 320/0/0
Tx timeouts 0,0,320,0,0,256 last cancelled message type 4514 dest 127
=== Network ===
Slowest loop: 4.19ms; fastest: 0.04ms
Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0), 0 sessions
HTTP sessions: 2 of 8
- Ethernet -
State: active
Error counts: 0 0 0 0 0
Socket states: 5 2 2 2 2 0 0 0

tmitch205

@phaedrux I was going to ask the same thing about static considering it's sitting on carpet. I have seen Duet 2 Wifi's lose their wifi connectivity due to this until they are restarted.

Michael Hathaway

Just a small update. I switched from Nylon to PETG. 250C/83C hotend/bed temps. I didn't change anything but the print temperatures. I was able to make 6 small and large successful prints using both Cura 5 and MatterControl slicers. Prints were perfect.

Now, loaded Nylon back on, but kept the bed temp the same for testing. 281C/83C. I will test different parameters.

droftarts

@michael-hathaway are Nylon and CF more prone to static buildup? Perhaps grounding the nozzle would help. Make sure the extruder motor is grounded, too. I still have no idea how it’s triggering a ‘manual reset’, unless a sudden zap is enough to drag the reset signal to ground.

Ian

Michael Hathaway

The printer is grounded and there is no carpet, only concrete in workshop. If static were the culprit, it would not print at lower temperatures.

It was 45-46°C in my workshop last week and I think the higher printing temperatures over loaded the board. While it was triggering a reset, one time it also triggered an emergency stop on its own.

It is now 26°C in the shop and it is printing my lower temp Nylon fine. I will load the HTNCF next and see if fails or continues to print.

droftarts

@michael-hathaway I asked @dc42 if he thought high ambient temperature causing the Duet MCU to overheat would trigger a reset that looks like a manual reset. He said "I think that's unlikely, but not impossible." Without knowing how hot the Duet board is getting (map the on-board MCU temp sensor to see a graph) that's difficult to know. An MCU reset or shutdown would be triggered somewhere above 85°C.

I know you said "the printer is grounded", but specifically are the metal parts of the hotend grounded? I still think a static shock is more likely, and grounding the hot end would eliminate this. You said you swapped out the PT1000 for a new one and got a different failure, so possibly static charge in the the hot end has arced through that and caused a reset. High ambient temperature + high temperature nozzle (this would lower humidity, making static worse) + possibly CF and Nylon that produce more static charge than PETG might be enough to reset the MCU.

However, @chrishamm thinks that a static shock to the temperature inputs may cause a MemoryProtectionFault reset (it does on the 6HC, not sure about the Mini 5+), which would show up in the M122 report.

One other question: How did the old Mini 5+ fail? Could it be related? Maybe the MCU got zapped?

Ian

Michael Hathaway

@droftarts I ordered a ring terminal to fit the hot end for grounding, will be here tomorrow. It was extremely humid here and hot.

All the boards show the same failure. I have had trouble free performance for 1.5 years. I have had the mini board shut down before when the chamber temperature went over 50C. This is an unusual heat wave in California. If this keeps up, I think I will install air conditioning in the workshop.

The other Matterhacker guys prefer their Azteeg boards. But for me, I only use Duet.

Michael Hathaway

Added electrical ground wire from the hotend to the frame and to electrical earth ground. Printer still failed prints.

Pulled printer from workshop into air conditioned building. Printer has produced several 10+ hour prints.

For fun, I added a copper heat sink to the MCU. Temperature now reading a -6.7°C drop. Probably not worth doing, but if a few degrees means the difference between another stall and not, then I am ok with it. I can now be part of the "stuck a heat sink on my MCU" fan club. lol

I think that I will make a new case cover that brings ambient air from outside the heat chamber to the Duet and then draw it back out again. Shouldn't be too difficult, I think two 60mm fans would work well.

infiniteloop

@michael-hathaway

I think that I will make a new case cover that brings ambient air from outside the heat chamber to the Duet and then draw it back out again. Shouldn't be too difficult, I think two 60mm fans would work well.

I often see housings with the Duet mounted near the bottom, cooling them from above. In your case, I’m not sure, but it is really essential to follow the explicit recommendations: cool the bottom of the board! Then, even a mediocre blower at low speed is sufficient.

Michael Hathaway

@infiniteloop I am not sure I follow you here. Why would I want to cool the bottom of the board? Are you talking about the back side of the board?

Cooling the back side of the board is for the stepper drivers as well as a couple of other items. I had a rather large fan cooling the back side of the board at the start of this. Didn't help what so ever. No, what ever is tripping the reset of the board is either on the front side or the board in it's entirety.

My board enclosure is located inside the heated print chamber. Blowing hot air over an overheated board is not going to be the answer for me. Bringing in cool air to cool the board and then exhausting it so that it doesn't cool the print chamber is what is needed.

My warped sense of humor here

infiniteloop

@michael-hathaway said in Duet mini 5+ freezes and shuts off heaters:

Are you talking about the back side of the board?

Sorry for my English: it's the back side what I mean.

Michael Hathaway

My original case had a 92mm fan on the front side and it was designed to blow air on the front and force the air around to the back side to cool the steppers. Still its hot air circulating and I need to do this a little differently this time. I didn't really have problems until we had a few really hot days and I was printing high temperature plastics, which made the chamber even hotter, surpassing the limits of the system.

droftarts

@michael-hathaway when you initially asked about this problem, there were a number of useful pieces of information that you weren’t forthcoming with: that the Duet (and PSU, I think) are mounted inside the heated chamber, the high ambient temperature at the time, printing high temperature materials. This lead to a focus on other factors that might cause the reset, rather than the obvious one; the board temperature.

What sort of temperature does the chamber get to? You are stressing the electronics on the board running it inside the enclosure. The MCU itself may be rated to 85C (operating temperature, not ambient temperature), but other components on the board may not be, and could be causing voltage fluctuations and the ‘phantom’ resets. I don’t think we publish a temperature range of operation for Duet boards (I’ll ask @dc42), but subjecting it to heat intentionally seems less than ideal. I think you have got away with it in past, but a combination of factors has pushed the board beyond its temperature limits. Is it possible to mount it outside the enclosure?

Ian

Michael Hathaway

@droftarts I agree with you completely.

The boards are not faulty, I am just pushing them to their limits. It's not really intentional though, I have just gotten away with it until now.

I don't think it is the MCU causing the shutdown, but something else on the board. I have printed no less than 20,000 prints on my original Duet mini 5. IMO it's way better than the American or any other boards on the market.

It's just a Prusa aluminum clad enclosure, many people use these. I have never pushed the chamber over 60°C and I know it was over 50 when I was having problems with the MCU in the 67-70C range. It was 48°C here in the shade and my workshop was close to that temperature. Both the combined high ambient temperature and the increase current through the board to bring the hotend up to 330C is what I think caused the resets/emergency shutdown.

Michael Hathaway

Will the Duet 6HC handle higher temperatures better than the mini 5+? Are the components on the board higher grade?

TLAS

@michael-hathaway said in Duet mini 5+ freezes and shuts off heaters:

The printer went 5 layers and stopped. I have no idea why it is freezing.

We’ll maybe you shouldn’t (should) leave it out in the cold? Sorry, couldn’t resist…

I’m fully certified to use dad jokes…
https://youtu.be/4CeWYM08s7A

Michael Hathaway

@tlas I don't wish to wire for external board. I am not the first person to print inside an enclosure. I just didn't know the thermal limits of this board until now. I will end up switching over to the 6HC as it seems to be more robust.

TLAS

@michael-hathaway
Mostly a joke there (board freezing… leaving it out in the cold…).

I can understand why folks would want to keep the boards in heated chambers.

FYI, bringing in a line of compressed air at ~10 psi is helpful to provide local cooling without impacting the overall chamber too much.