@dc42 hi Dave, I have dialed them down from 2A to 1.6A

Ok, problem appears to be solved.
All carriages removed, cleaned and reinstated. Belt tensions checked and stepper motor current reduced by 80%.
Added always on 40x40 cooling fan to underside of board.
Thanks for all the comments!

@infiniteloop
Ok, problem appears to be solved.
All carriages removed, cleaned and reinstated. Belt tensions checked and stepper motor current reduced by 80%.
Added always on 40x40 cooling fan to underside of board.
Thanks for all the comments!

@Phaedrux I do have cooling, but recent posts will lead me to believe it is nowhere near enough. Original fan is a proxy llitle 20x20 fan, just ordered a 40x40 and a proper cooling channel across the drivers.
Yes they got very hot. I used a Fluke thermal camera and they reached 85°C (185F).

@Phaedrux thanks for the response.
No, I am sure the skipping happened after i had the warning
I am in the process of disasembly and will be going over each and every component.
Thanks again!

Hi all

My Delta printer, with Duet WiFi 2, have started to skip steps. This is evident in layer shift. I suspect damaged stepper driver(s), as I once only received an error message of over temperature on stepper driver 1. My question is, will a once off event on over temperature cause stepper driver damage? And, I assume driver damage will cause step skipping?

Thanks!

@Phaedrux hi, and thanks for responding.
Yes, I can move in all directions, print starts out good but goes south pretty quickly.
I have acrive cooling, but after recent research is nowhere near enough.
With PETG, I bumped the heatbed up from 55C to 85C, and I made 100% sure I restored all PLA settings.

Moving on, I have the board out and will get much better cooling to the underside if the board.

I will revert when i know more.

Hi all. I have a Delta, and using a Duet WiFi 2. I have been printing PLA with great sucess. I then tried PETG, and I quickly received an error message that Driver 1 is Over Temperature.
I immediately shut down, thought nothing of it and and blamed the elevated bed temperatures for this alarm. A couple days later i started up again, tossed the PETG in the bin and went back to PLA. Although I don't get the error again, I fear that I bricked my Duet. First layer infill prints over the perimeter by a good 2mm, and 2nd layer rips the first layer no matter what I do with nozzle height.
Would the heat / alarm have aused damaged the driver that now cause the stepper to skip steps?
How do I test for step skipping?

m122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 3.4.6 (2023-07-21 14:08:28) running on Duet WiFi 1.0 or 1.01
Board ID: 08D6M-91AST-L23S4-7J1DJ-3S86M-1QX5K
Used output buffers: 1 of 26 (13 max)
=== RTOS ===
Static ram: 23896
Dynamic ram: 74156 of which 12 recycled
Never used RAM 14016, free system stack 184 words
Tasks: NETWORK(notifyWait,14.0%,242) HEAT(notifyWait,0.0%,333) Move(notifyWait,0.0%,363) MAIN(running,86.0%,458) IDLE(ready,0.0%,30), total 100.0%
Owned mutexes:
=== Platform ===
Last reset 00:06:04 ago, cause: power up
Last software reset at 2024-04-07 17:05, reason: User, GCodes spinning, available RAM 13920, slot 1
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0041f000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
Step timer max interval 0
MCU temperature: min 30.0, current 30.9, max 31.2
Supply voltage: min 23.7, current 23.8, max 24.0, 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 n/a
Driver 1: standstill, SG min n/a
Driver 2: standstill, SG min n/a
Driver 3: standstill, SG min n/a
Driver 4: standstill, SG min n/a
Driver 5:
Driver 6:
Driver 7:
Driver 8:
Driver 9:
Driver 10:
Driver 11:
Date/time: 2024-04-08 15:43:58
Cache data hit count 4294967295
Slowest loop: 6.23ms; fastest: 0.18ms
I2C nak errors 0, send timeouts 0, receive timeouts 0, finishTimeouts 0, resets 0
=== Storage ===
Free file entries: 10
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest read time 0.5ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 83, segments created 0, maxWait 0ms, bed compensation in use: none, comp offset 0.000
=== MainDDARing ===
Scheduled moves 0, completed 0, 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
=== 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
Daemon is idle in state(s) 0
Autopause is idle in state(s) 0
Code queue is empty
=== Network ===
Slowest loop: 101.56ms; fastest: 0.08ms
Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
HTTP sessions: 1 of 8
= WiFi =
Interface state: active
Module is providing access point
Failed messages: pending 0, notready 0, noresp 2
WiFi firmware version 1.27
WiFi MAC address a2:20:a6:19:26:75
WiFi Vcc 3.36, reset reason Turned on by main processor
WiFi flash size 4194304, free heap 20512
WiFi IP address 10.1.1.2
Connected clients 1
Clock register 00002002
Socket states: 0 0 0 0 0 0 0 0

@airscapes where did you get the latest dwc zip file? I am trying to update mine.