Duet Wifi board not powering on with 24v in, fine with USB

[rschlachter]

I finally wired everything up on my printer and connected everything to the board.
Sadly, the PSU light doesn't go green and nothing lights up on the Duet Wifi board.

I removed every connection from the board and it didn't take long.
I verified that coming out of the PSU I have 24v.
Powered off, connected to the board, and nothing.
I have my fan jumper set to 24v since that's what my fans are.
I have the 5v jumper on internal
I checked the three fuses and they all look fine.

I disconnected the 24v and plugged the board into USB and things seem fine.

m122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 3.5.4 (2024-11-24 10:43:42) running on Duet WiFi 1.02 or later
Board ID: 08DGM-917NK-F2MS4-7JTDJ-3SD6M-KDT8F
Used output buffers: 1 of 26 (14 max)
=== RTOS ===
Static ram: 23488
Dynamic ram: 71100 of which 0 recycled
Never used RAM 18888, free system stack 186 words
Tasks: NETWORK(1,ready,13.2%,217) HEAT(3,nWait 5,0.0%,378) Move(4,nWait 5,0.0%,361) MAIN(1,running,84.4%,946) IDLE(0,ready,2.4%,29), total 100.0%
Owned mutexes: WiFi(NETWORK) USB(MAIN)
=== Platform ===
Last reset 00:00:40 ago, cause: power up
Last software reset details not available
Error status: 0x00
MCU temperature: min 24.8, current 27.2, max 27.7
Supply voltage: min 1.4, current 1.7, max 1.8, under voltage events: 0, over voltage events: 0, power good: no
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: ok, SG min n/a
Driver 1: ok, SG min n/a
Driver 2: ok, SG min n/a
Driver 3: ok, SG min n/a
Driver 4: ok, SG min n/a
Driver 5: 
Driver 6: 
Driver 7: 
Driver 8: 
Driver 9: 
Driver 10: 
Driver 11: 
Date/time: 2025-02-19 17:55:06
Cache data hit count 1641897346
Slowest loop: 5.69ms; fastest: 0.14ms
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 3.5ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 83, segments created 0, maxWait 0ms, bed compensation in use: none, height map offset 0.000, max steps late 0, min interval 0, bad calcs 0, ebfmin 0.00, ebfmax 0.00
no step interrupt scheduled
Moves shaped first try 0, on retry 0, too short 0, wrong shape 0, maybepossible 0
=== DDARing 0 ===
Scheduled moves 0, completed 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters -1 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
=== GCodes ===
Movement locks 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 ready with "m122" 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
Q0 segments left 0
Code queue 0 is empty
=== Network ===
Slowest loop: 6.14ms; fastest: 0.00ms
Responder states: HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
HTTP sessions: 1 of 8
=== WiFi ===
Interface state: active
Module is connected to access point 
Failed messages: pending 0, notrdy 0, noresp 0
Firmware version 2.2.1
MAC address 60:01:94:2e:9a:74
Module reset reason: Turned on by main processor, Vcc 3.43, flash size 4194304, free heap 42772
WiFi IP address 192.168.50.88
Signal strength -54dBm, channel 1, mode 802.11n, reconnections 0
Clock register 00002002
Socket states: 0 0 0 0 0 0 0 0
ok

[Phaedrux]

You're getting no LED lights at all when only 24v is supplied?

[rschlachter]

@Phaedrux Correct. No LED lights at all on the Duet board with only 24v supplied.
FWIW, the green light on the power supply flashes 1 time every few seconds. If I remove the wires from the Duet board, the light on the power supply is bright green and steady.

Not sure it was a good idea, but I connected it to both USB and 24v in. It just kept saying WiFi module started, flicking on an off. I did sneak in an m122, but I'm not sure it's trustworthy.

m122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 3.5.4 (2024-11-24 10:43:42) running on Duet WiFi 1.02 or later
Board ID: 08DGM-917NK-F2MS4-7JTDJ-3SD6M-KDT8F
Used output buffers: 1 of 26 (11 max)
=== RTOS ===
Static ram: 23488
Dynamic ram: 71076 of which 0 recycled
Never used RAM 18912, free system stack 186 words
Tasks: NETWORK(1,ready,60.8%,462) HEAT(3,nWait 5,0.0%,385) Move(4,nWait 5,0.0%,361) MAIN(1,running,39.2%,792) IDLE(0,ready,0.0%,29), total 100.0%
Owned mutexes: USB(MAIN)
=== Platform ===
Last reset 00:00:02 ago, cause: power up
Last software reset details not available
Error status: 0x00
MCU temperature: min 27.7, current 27.8, max 27.8
Supply voltage: min 0.1, current 0.2, max 0.2, under voltage events: 0, over voltage events: 0, power good: no
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: ok, SG min n/a
Driver 1: ok, SG min n/a
Driver 2: ok, SG min n/a
Driver 3: ok, SG min n/a
Driver 4: ok, SG min n/a
Driver 5: 
Driver 6: 
Driver 7: 
Driver 8: 
Driver 9: 
Driver 10: 
Driver 11: 
Date/time: 1970-01-01 00:00:00
Cache data hit count 116591638
Slowest loop: 0.22ms; fastest: 0.14ms
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 0.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 83, segments created 0, maxWait 0ms, bed compensation in use: none, height map offset 0.000, max steps late 0, min interval 0, bad calcs 0, ebfmin 0.00, ebfmax 0.00
no step interrupt scheduled
Moves shaped first try 0, on retry 0, too short 0, wrong shape 0, maybepossible 0
=== DDARing 0 ===
Scheduled moves 0, completed 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters -1 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
=== GCodes ===
Movement locks 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 ready with "m122" 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
Q0 segments left 0
Code queue 0 is empty
=== Network ===
Slowest loop: 0.02ms; fastest: 0.00ms
Responder states: HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
HTTP sessions: 0 of 8
=== WiFi ===
Interface state: changingMode
Module is idle
Failed messages: pending 0, notrdy 0, noresp 1
Failed to get WiFi status
Socket states: 0 0 0 0 0 0 0 0
ok
WiFi module started
WiFi module started
WiFi module started
WiFi module started
WiFi module started

[rschlachter]

Just to provide some additional context, the power supply is the old MW LRS-200-24 from the DI3+ as well. It ran everything fine before the frame rebuild (though the bed was different). It also was working fine prior to connecting the additional wires. I left it on and running for a couple of days just to see that the DWC stayed connected after my network issues.

I found some other folks in the Voron space who use this power supply and said it's a built in safety feature. If it detects something is shorted out, it won't supply voltage. Given the behavior I'm seeing when the leads are connected to the board vs not, I suspect this is what's happening. What I'm not sure about is how/where there would be a short on the board. No obvious signs of one.
If anything was connected I was immediately suspect my wiring.

Combing through the forums I found one other post with something similar. The user tried a new power supply and that seemed to solve the issue. I ordered a new LRS-350-24 last night. Should be here today so I'll try it out.

What confuses me here is that the board seems fine when connected to the PC via USB. So I don't think the board is dead.

I guess my hope/thought right now is that the power supply short protection feature is faulty and that's the cause, but I'm also a bit skeptical because it was working prior to connecting all the motors, fans, etc, so it could be a short somehow?

Here are a few pics. The first is the switch wiring. Old pic before I pulled it out of the old frame, but wired the same.

[droftarts]

@rschlachter I can't see anything obviously wrong with your board. Perhaps double check that the long pins on the back of board are not touching the mounting plate. You could remove the three fuses, and apply power, then replace them individually to see if any particular circuit is causing the PSU to detect a fault.

Ian

[rschlachter]

@droftarts Interesting. The 7.5a fuse seems to be the one. Meaning that it seems there's a short either somewhere along the steppers or the extruder or extruder heaters? Everything looks fine...

[droftarts]

@rschlachter V_Fused (that the 7.5A fuse provides) supplies most of the board, including the 5V regulator, so the fault could be anywhere. Unfortunately there's not much you can check, except to see if things get hot when you connect a PSU that doesn't cut out.

This photo makes it look like there's something in the expansion slot? But could be a reflection.

Ian

[dc42]

@rschlachter the most likely things to short out the power after the 7.5A fuse are the 5V regulator U3 or one of the stepper drivers. U3 looks OK on your photo although it's not detailed enough for me to be sure. OTOH the centre stepper driver doesn't look right, the Trinamic logo seems to have disappeared.

[droftarts]

@dc42 said in Duet Wifi board not powering on with 24v in, fine with USB:

OTOH the centre stepper driver doesn't look right, the Trinamic logo seems to have disappeared.

Good spot! Definitely looks like it’s had some heat.

Ian

[rschlachter]

@droftarts I think that's just a weird reflection.

@dc42 Yes, it does seem like that one is darker. I would have thought that would have reported bad when plugged in to USB, but I suppose it must not.

I suppose. I mean worst case, that got reversed in the wiring. The old stepper motors aren't marked well.

Bummer. I guess that's the end for this.