Duet3D 6HC displayed voltage drop from 24v input to 16v onboard

jerryjs8

Hello Forum Gurus!

I have a "slight" problem with my Duet 3 6HC mainboard

The mainboard itself displays a supply voltage of 16.2V in the Web Control window, but the Duet3D Mainboard 6HC is supplied with 24 V via a switching power supply.

This hasn't always been the case, and lately it's been causing some problems...

On the one hand, this means that the connected stepper motors have less power due to the lower voltage, for which I decreased the acceleration settings to stop loosing steps. In addition, macros are sporadically executed incorrectly and sometimes lead to dangerous situations!

The troubleshooting in the Duet3D forum shows the solution by replacing SMD resistors on the mainboard, but since the board is still under warranty, I don't want to go soldering anything.

Is there anything else I can do about this, or do I absolutely need to replace it with a new unit?

I would greatly appreciate any input, since I'm at a loss...

Kind regards,
Joseph

dc42

@jerryjs8 I think the issue is that the version of RRF you are running is too old to recognise the 1.02 revision of the 6HC, which I presume is the revision you have. Please upgrade to 3.4.6.

fcwilt

@jerryjs8

Have you verified the output of the power supply is 24 when the Duet reports 16?

Frederick

dc42

@jerryjs8 said in Duet3D 6HC displayed voltage drop from 24v input to 16v onboard:

The mainboard itself displays a supply voltage of 16.2V in the Web Control window, but the Duet3D Mainboard 6HC is supplied with 24 V via a switching power supply.

Does it always display the VIN voltage as 16V, or does it display the minimum recorded VIN voltage as 16V?

If it always displays 16V when the VIN voltage is actually 24V then that usually indicates that you are feeding 5V to the 3.3V rail. To check that, disconnect everything from the 6HC IO and SPI daughter board connectors and use M122 to check the reported VIN voltage again.

The 6HC should report the VIN voltage to within a few percent. No need to change any resistors, assuming it's a genuine Duet3D board.

jerryjs8

@fcwilt Hello Frederick, and yes, the power supply is giving 24v to the Duet 3 input bus.

@dc42 Hello Dave, thanks for such a quick reply!

First off, it is a genuine Duet3D board

In the Duet webcontrol the status sensor reports a constant 16.2v, and that value doesn't change.

I have the board on a test bench with nothing else plugged in except a laboratory power supply feeding it 24 volts and the ethernet cable. Running M122 gives me the following:

4.1.2024, 16:20:15 m122
=== Diagnostics ===
RepRapFirmware for Duet 3 MB6HC version 3.4.0 (2022-03-15 18:57:24) running on Duet 3 MB6HC v1.01 or later (standalone mode)
Board ID: 08DJM-956BA-NA3TJ-6J1FD-3S06Q-KU86S
Used output buffers: 3 of 40 (14 max)
=== RTOS ===
Static ram: 151000
Dynamic ram: 95476 of which 0 recycled
Never used RAM 104196, free system stack 206 words
Tasks: NETWORK(ready,15.0%,227) ETHERNET(notifyWait,0.2%,173) HEAT(notifyWait,0.0%,373) Move(notifyWait,0.0%,352) CanReceiv(notifyWait,0.0%,944) CanSender(notifyWait,0.0%,374) CanClock(delaying,0.0%,333) TMC(notifyWait,7.3%,92) MAIN(running,39.4%,1101) IDLE(ready,38.1%,30), total 100.0%
Owned mutexes:
=== Platform ===
Last reset 00:00:35 ago, cause: power up
Last software reset at 2023-12-14 14:08, reason: User, GCodes spinning, available RAM 100092, slot 0
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00400000 BFAR 0x00000000 SP 0x00000000 Task MAIN Freestk 0 n/a
Error status: 0x00
Step timer max interval 133
MCU temperature: min 18.2, current 28.5, max 28.5
Supply voltage: min 16.0, current 16.1, max 16.2, under voltage events: 0, over voltage events: 0, power good: yes
12V rail voltage: min 12.1, current 12.3, max 12.4, under voltage events: 0
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, mspos 8, reads 65279, writes 14 timeouts 0
Driver 1: standstill, SG min 0, mspos 8, reads 65279, writes 14 timeouts 0
Driver 2: standstill, SG min 0, mspos 8, reads 65279, writes 14 timeouts 0
Driver 3: standstill, SG min 0, mspos 8, reads 65280, writes 14 timeouts 0
Driver 4: standstill, SG min 0, mspos 8, reads 65280, writes 14 timeouts 0
Driver 5: standstill, SG min 0, mspos 8, reads 65283, writes 11 timeouts 0
Date/time: 2024-01-04 16:20:14
Slowest loop: 6.64ms; fastest: 0.05ms
=== Storage ===
Free file entries: 10
SD card 0 detected, interface speed: 25.0MBytes/sec
SD card longest read time 2.4ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 125, 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 -1 -1 -1 -1 -1 -1 -1 -1 -1 -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
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 189, received 0, lost 0, boc 0
Longest wait 0ms for reply type 0, peak Tx sync delay 0, free buffers 50 (min 49), ts 177/0/0
Tx timeouts 0,0,176,11,0,0 last cancelled message type 30 dest 127
=== Network ===
Slowest loop: 7.52ms; fastest: 0.02ms
Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0), 0 sessions Telnet(0), 0 sessions
HTTP sessions: 1 of 8

Ethernet -
State: active
Error counts: 0 0 1 0 0
Socket states: 5 2 2 2 2 0 0 0

jay_s_uk

@jerryjs8 when and where did you purchase the board?

dc42

@jerryjs8 I think the issue is that the version of RRF you are running is too old to recognise the 1.02 revision of the 6HC, which I presume is the revision you have. Please upgrade to 3.4.6.

jerryjs8

@jay_s_uk I got it one year ago.

@dc42 The upgrade to 3.4.6 did the trick, thanks for the suggestion!!!

Problem solved