Duet3 6HC Ratrig motor stopped working

nerathul

Hey Duet forum,

we bought a ratrig v-core3 at our university and for about 3 months now it worked with the duet3 6HC like a charm. Now one of the 3 Z-axis motors stopped working and the console reported the error "Error: short-to-ground reported by driver(s) 1". Also at this point the motor was boiling hot.
The mainboard version and the m122 is:

M122
=== Diagnostics ===
RepRapFirmware for Duet 3 MB6HC version 3.3 (2021-06-15 21:45:47) running on Duet 3 MB6HC v1.01 or later (SBC mode)
Board ID: 08DJM-956BA-NA3TN-6J1DD-3SD6T-KABUS
Used output buffers: 1 of 40 (10 max)
=== RTOS ===
Static ram: 150904
Dynamic ram: 61592 of which 628 recycled
Never used RAM 141068, free system stack 219 words
Tasks: SBC(ready,5.0%,338) HEAT(delaying,0.0%,331) Move(notifyWait,0.0%,352) CanReceiv(notifyWait,0.0%,944) CanSender(notifyWait,0.0%,374) CanClock(delaying,0.0%,333) TMC(notifyWait,7.1%,93) MAIN(running,87.8%,922) IDLE(ready,0.0%,29), total 100.0%
Owned mutexes: HTTP(MAIN)
=== Platform ===
Last reset 00:22:48 ago, cause: power up
Last software reset at 2022-03-31 13:07, reason: User, GCodes spinning, available RAM 141068, slot 0
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0x00000000 SP 0x00000000 Task SBC Freestk 0 n/a
Error status: 0x00
Step timer max interval 177
MCU temperature: min 22.8, current 40.6, max 40.8
Supply voltage: min 23.9, current 23.9, max 23.9, under voltage events: 0, over voltage events: 0, power good: yes
12V rail voltage: min 12.1, current 12.2, max 12.2, under voltage events: 0
Heap OK, handles allocated/used 0/0, heap memory allocated/used/recyclable 0/0/0, gc cycles 0
Driver 0: position 0, standstill, reads 59730, writes 15 timeouts 0, SG min/max 0/0
Driver 1: position 0, standstill, reads 59730, writes 15 timeouts 0, SG min/max 0/0
Driver 2: position 0, standstill, reads 59730, writes 15 timeouts 0, SG min/max 0/0
Driver 3: position 0, standstill, reads 59730, writes 15 timeouts 0, SG min/max 0/0
Driver 4: position 0, standstill, reads 59730, writes 15 timeouts 0, SG min/max 0/0
Driver 5: position 0, standstill, reads 59731, writes 15 timeouts 0, SG min/max 0/0
Date/time: 2022-04-04 09:32:10
Slowest loop: 0.46ms; fastest: 0.05ms
=== Storage ===
Free file entries: 10
SD card 0 not detected, interface speed: 37.5MBytes/sec
SD card longest read time 0.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 125, maxWait 0ms, bed compensation in use: mesh, comp offset 0.000
=== MainDDARing ===
Scheduled moves 0, completed moves 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== AuxDDARing ===
Scheduled moves 0, completed moves 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters = 0 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1, chamberHeaters = -1 -1 -1 -1
=== GCodes ===
Segments left: 0
Movement lock held by null
HTTP* is doing "M122" 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.
=== CAN ===
Messages queued 12193, received 0, lost 0, longest wait 0ms for reply type 0, peak Tx sync delay 0, free buffers 49 (min 49), ts 6843/0/0
Tx timeouts 0,0,6842,0,0,5349 last cancelled message type 4514 dest 127

=== SBC interface ===
State: 4, failed transfers: 3, checksum errors: 0
Last transfer: 2ms ago
RX/TX seq numbers: 48296/48453
SPI underruns 0, overruns 0
Disconnects: 1, timeouts: 0, IAP RAM available 0x2c83c
Buffer RX/TX: 0/0-0
=== Duet Control Server ===
Duet Control Server v3.3.0
Code buffer space: 4096
Configured SPI speed: 8000000Hz
Full transfers per second: 0.15, max wait times: 4.5ms/0.0ms
Codes per second: 0.00
Maximum length of RX/TX data transfers: 2952/64

Here our config.g file:
config.g
there is one change I did since the motor stopped working I changed the stepper mode from stealthchop (set in the guide of ratrig) to spreadcycle as in on post in this forum mentioned for faster printers.

Now my problem is we don't know if the stepper could got damaged by the motor which not worked as the printer got a print job but as the problem was noticed the job immediately got stopped (about 1 min he ran the job).

Should the board be changed?

Already thanks to everyone whos helping.

Greetings,
Leon Kraft aka nerathul

oliof

Hi,

you could check whether the driver gets hot just after turning on the machine, or whether you see physical damage (a crater) on the driver chip.

You could try to use the driver on another stepper by changing the stepper assignment (lines 13 to 19 in your config.g) and swapping the wires. Speaking of the wires, check that the crimps are good and the stepper wires aren't damaged.

A Former User

This post is deleted!

oliof

@arnold_r_clark thank you for pointing this one out, it has infact escaped several people looking at the configuration again. I'll get it fixed.

droftarts

@oliof This one keeps coming back...
https://forum.duet3d.com/post/273498 (and your response in the thread https://forum.duet3d.com/post/273579)
https://forum.duet3d.com/post/273520
https://forum.duet3d.com/post/273534
https://forum.duet3d.com/post/276664
and there's probably more...

Ian

nerathul

Thanks to @Arnold_R_Clark and @oliof for the quick response.
The crimps are all good, i will change the gcode as soon as possible.
The driver gets a bit "hot" around 60C the others stay cool. I already tried
to use the stepper driver on another of the z motors and its doing fine only
the temps are not quiet normal I think.

But with the temprature fault I think it would be good just in case to change
for the faulty driver. Or do you think makes more sense just to add active cooling
for the one driver?

oliof

@droftarts I do assume there are more, but as I said, these escaped my attention until now. I'll take a closer look.

A Former User

This post is deleted!

droftarts

@nerathul back on-topic, check the resistance of each phase of the stepper motor with a multimeter. It could be that the wiring internally has failed; rare, but I've had this happen. See https://docs.duet3d.com/User_manual/Connecting_hardware/Motors_connecting#identifying-the-stepper-motor-phases
The resistance should be about the same for each phase. Check against another motor or the motor specification. It's not always the Duet that fails!

Ian