I will add few cents to this discussion:
I supply 37V to my v1.0 6HC Duet:
https://forum.duet3d.com/topic/26758/32-4v-input-instead-of-32v/2?_=1659258404908
If you want to know more about steppers, check this video out:
https://www.youtube.com/watch?v=lftsMrksdTA&list=PLWQs4VcXB7unGrcCVibcisuvt0Hamxb4d&index=21
@phaedrux Nope, it did not. That was first thing that I suspected. I've checked leadscrews, linear rods and bearings, all is fine. Even if anything would be damaged, it doesn't explain noisy motors when I test them on my desk. Please check my videos.
Here is second video with "new" motors:
Two Stepper motors in parallel - weird noise Part 2
I think that new motors behaved the same way as ones before.
It is possible that back EMF from 2 motors is messing with current control of SpreadCycle, because when one motor stopped turning the other one went way quieter. But question remains, why it was ok before my "crash"?
It would be nice if anyone could reproduce testing of 2 or 3 motors connected in parallel.
@jumpedwithbothfeet Thanks for your reply. I've checked that all stepper motors TDS current rating is in RMS, in DWC we set peak value. So 2A peak is 1,418A RMS, this 80% max current is just to lower temperature of a motor. From my knowledge every motor max current is based on max winding temperature and heat dissipation. Every motor can be overloaded, sometimes as much as 5x.
I actually have 2 more motors which are very similar, Model 17PM-K940-P7VS (motors on video are 17PM-K940-P6VS). According to a seller those motors are basically the same. I've used them on XY axis before with no issues. I will test them the same way on new video.
Edit:
All 5 motors have the same phase resistance of around 1,65Ω. I've opened motor that was on left side of a printer, windings looked fine so I would rule out windings failure. The only thing that comes to mind how motor could be damaged is related do permanently disturbed magnetisation of rotor. But that would be hard to confirm. And those two motors tested work fine when they are alone.
Here is a video recorded today - sound effects of two motors connected in parallel: Two Stepper motors in parallel - weird noise
@jumpedwithbothfeet Z motors were connected to Driver 2 before and during crash. Before crash 3 motors together were working fine on F3000 and 5A. After crash they were loud. I tested them on driver 2 and later on driver 5 with no difference.
On video motors are tested on driver 2 of Duet.
And I've forgot to mention, I got Duet 6HC, powered by 37,7V.
Hello everyone,
TL;DR: Motors started to vibrate weirdly after stall during lowering the bed. 3 motors were connected in parallel to one driver, and I've forgot to increase current in config for 3 motors instead of 1.
Full story:
I was assembling lead screws and linear rods (triple Z axis, 700mm travel) for my printer. I hope you can see it well enough on picture below:
At first I've tested only 1 Z axis with 1 motor connected to driver. I've settled on F3000 (50mm/s) and 2A peak current (1,42A RMS). So it is fast enough to travel those 700mm and not so loud - except typical high pith noise of low quality motors . Motors are "Minebea", Model: 17PM-K940-P6VS, 1,8°, 1,5A, 0,45Nm and measured phase resistance of around 1,65Ω, unfortunately I couldn't find any documentation of this motor so inductance is unknown.
Since everything looked fine I've assembled all 3 Z axis and T frame with kinematic coupling for the head bed (as seen on picture). Next all 3 motors were connected in parallel to one driver. Did few more up-down travels of this assembly to check it out. All being fine I thought "ok, now lets throw my 516x516x10 aluminium on it and see hot it fits"
And as you can guess, on first down move (I think order was 100mm) I've heard loud noise of stalled motors. I didn't have my E stop in hand so it lasted for 2 seconds. In reality all motors stalled in a sequence, cause bed was heavily tilted to one side (around 50mm). To correct my mistake, I've cut power, moved bed to kind of levelled state, restarter board and set higher current for Z to be 5A peak (3,54A RMS).
To my surprise motors were now loud as hell, whole printer was shaking. So I took bed of from T frame, but it didn't change anything. I did some test and it looks like something permanently changed.
When I power only 1 motor (F3000 (50mm/s) and 2A peak current) it works fine (at least as I can remember how it was before crash). But when 2 motors are connected in parallel, with 2x current, both of them are very loud and shaking. I lowered speed to F1000. This decreased noise a lot but when I was holding motor in hand I could feel irregular "grinding or crunching like" vibrations. But when the same motor is connected alone I don't feel this "grinding". I've teardown this motor but didn't found anything out of order, bearings were fine etc.
My quick conclusion was that driver was damaged. So I've redo tests on different driver but no change was observed.
Next I've checked setting in config to see any changes, but all drivers are working in default spread cycle.
I know that those motors aren't highest quality, and are for test purposes only (I am planning on getting my hands on something name brand later). But apart from that, what happened (very loud motors after crash) is a mystery for me and shouldn't happen. I would like to find the cause of this instead of "just get better motors".
I run latest firmware and DWC, my config below:
; Configuration file for Duet 3 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.1.10 on Fri Dec 11 2020 19:50:46 GMT+0100 (Central European Standard Time)
; General preferences
G90 ; send absolute coordinates...
M83 ; ...but relative extruder moves
M550 P"Arato" ; set printer name
M669 K1 ; select CoreXY mode
M955 P0 I25 S1600 R16 C"spi.cs3+spi.cs2" ; all wires connected to temp DB connector - Accelerometer creation
; Network
M552 P0.0.0.0 S1 ; enable network and acquire dynamic address via DHCP
M586 P0 S1 ; enable HTTP
M586 P1 S0 ; disable FTP
M586 P2 S0 ; disable Telnet
; Drives
M569 P0.0 S1 ; physical drive 0.0 goes forwards lewy motor
M569 P0.1 S1 ; physical drive 0.1 goes forwards prawy motor
M569 P0.2 S0 ; physical drive 0.2 goes backwards Z motors tymczasowo
M569 P0.3 S0 ; physical drive 0.3 goes backwards Extruder?
M569 P0.5 S1 ; T locking pin
; test drivera Z
;M569 P0.5 S0 ; physical drive 0.2 goes backwards
M584 X0.0 Y0.1 Z0.2 E0.3 ;C0.5 ; set drive mapping
; test drivera Z
;M584 X0.0 Y0.1 Z0.5 ;E0.3 ;C0.5 ; set drive mapping
M350 X16 Y16 Z16 E16 I1 ; configure microstepping with interpolation
M350 C16 I1
M92 X100.00 Y100.00 Z1600.00 E1376 C100 ; set steps per mm
M566 X2000.00 Y2000.00 Z60.00 E120.00 C20 ; set maximum instantaneous speed changes (mm/min)
;M203 X60000.00 Y60000.00 Z200.00 E2400.00 C6000 ; set maximum speeds (mm/min)
M203 X30000.00 Y30000.00 Z1000.00 E3000.00 C600 ; set maximum speeds (mm/min)
;M201 X40000.00 Y40000.00 Z40.00 E10000.00 C1000 ; set accelerations (mm/s^2)
M201 X4000.00 Y4000.00 Z120.00 E10000.00 C500 ; set accelerations (mm/s^2)
;M204 P30000 T50000 ; set accelerations (mm/s^2) P- printing T- travel
M204 P3000 T5000 ; set accelerations (mm/s^2) P- printing T- travel
M906 X4000 Y4000 Z2000 E850 C600 I30 ; set motor currents (Peak mA) and motor idle factor in per cent
M84 S1 ; Set idle timeout
; Axis Limits
;M208 X0 Y0 Z0 S1 ; set axis minima
;M208 X568 Y565 Z500 S0 ; set axis maxima
; Print area (0,0) - (500,500)
M208 S1 X-34 Y-4 Z0 ; set axis lower limits
M208 S0 X534 Y562 Z500 ; set axis upper limits
; Endstops
M574 X1 S1 P"io0.in" ; configure active-high endstop for low end on X via pin io0.in
M574 Y1 S1 P"io1.in" ; configure active-high endstop for low end on Y via pin io1.in
M574 Z1 S2 ; configure Z-probe endstop for low end on Z
; M574 C1 S3
; Z-Probe
M558 P5 C"^io2.in" H5 F600 T30000 ; set Z probe type to switch and the dive height + speeds
G31 P500 X0 Y0 Z2.5 ; set Z probe trigger value, offset and trigger height
M557 X0:500 Y0:500 S250 ; define mesh grid
;Stall Detection
; M915 C S6 F0 H200 R0 ; Coupler
; Heaters
M308 S0 P"temp0" Y"thermistor" T100000 B4138 ; configure sensor 0 as thermistor on pin temp0
M950 H0 C"out0" T0 ; create bed heater output on out0 and map it to sensor 0
M307 H0 B1 S1.00 ; enable bang-bang mode for the bed heater and set PWM limit
M140 H0 ; map heated bed to heater 0
M143 H0 S120 ; set temperature limit for heater 0 to 120C
M308 S1 P"temp1" Y"thermistor" T100000 B4138 ; configure sensor 1 as thermistor on pin temp1
M950 H1 C"out1" T1 ; create nozzle heater output on out1 and map it to sensor 1
M307 H1 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit
M143 H1 S280 ; set temperature limit for heater 1 to 280C
; Fans
M950 F0 C"out4" Q500 ; create fan 0 on pin out4 and set its frequency
M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"out5" Q500 ; create fan 1 on pin out5 and set its frequency
M106 P1 S1 H-1 ; set fan 1 value. Thermostatic control is turned off
; Tools
M563 P0 D0 H1 F0 ; define tool 0
G10 P0 X0 Y0 Z0 ; set tool 0 axis offsets
G10 P0 R0 S0 ; set initial tool 0 active and standby temperatures to 0C
; Custom settings are not defined
M950 J1 C"io8.in" ; E STOP - stopping movements
M581 P1 T0 S1 R0 ;
It depends on if you want to control all 4 motors individually for bed traming. If yes, every motor needs to be connected to individual stepper driver. So each will have its own set of parameters, which will be identical if you use the same kind of motors.
Other option is that all motors will be working together as one and bed traming will be done manually by turning screws of each motor. In this scenario all motors could be connected to 1 stepper driver. There are actually 3 ways to connect 4 motors to 1 driver.
I personally have 3 motors, each on separate driver which is best. I experimented on three 1,8A motors connected in parallel on 6HC board which worked on dry runs (but I also work on 37V supply). I don't know about that during printing.
I hope that will give you general idea.
There was a topic on forum about different wiring the accelerometer when using daughter board because this board shifts few pins around. Try look for that.
I asked about similar feature here:Terminate movement but not by M112
@sinole You are right, it is SDO, as documentation says here:
https://docs.duet3d.com/User_manual/Connecting_hardware/Sensors_Accelerometer
I've miss typed, gonna edit my post above.
@dizzwold You can use online calculators or formulas to get resistance of a wire. What is important is to choose suitable cable size depending on motor current (RMS value) and cable length.
For example, 22 AWG (+- 0,326mm2) wire of 2m length (1m distance from Duet) has 0,1Ohm resistance in 30C. If you will pass 2A RMS it will result in 0,2V (U=IR) drop, and about 0,4W (P=UI or RII) of heat released, which isn't a lot, even on 3m from duet (6m of wire total for 1 phase of motor) 0,6V drop and 1,2W loss isn't that much. If you use 12V you might want to get a little thicker cable for smaller voltage drop.
Twisting wire pair for motor phase as @jay_s_uk said will reduce inductance which is important for high speeds, this is the same as most people are using low inductance motors.
I also put small ferrite cores on all 4 wires per motor close to duet, just in case of unwanted EMI.
Hello. I would like to terminate any current moves (printing, running macro, movements from Dashboard etc) but without loosing current position (still being homed). M112 will stop all movements but also shut down Duet.
Example:
I am running series of macros for testing purposes, but I've started wrong macro that will crash on items on bed or take a long time to complete. I don't want to reset Duet because I still got data to extract and I don't want to set up everything again for testing.
I searched Forum and Wiki but all I found is that I can use trigger that will execute after all commands from buffer.
Any solution for that?
I was fighting with my accelerometer yesterday - LIS3DSH.
1st it wasn't recognised on selected port, 680Ohm resistor on SDA SDO line helped.
2nd I wanted to get some data to check if gravity is sensed but got similar error that I can't collect data. I didn't found any info on forum or wiki. Turned out that data can be collected after I homed the printer.
Thank you for clarification, I was concerned that I've overstressed capacitors which would lead to nasty failure.
Now I am relived 
Kind Regards,
Thanks for info. 220uF caps for TMC's are marked 50V on schematic and their markings are "220 50A RN8" (I guess that 50 corresponds to 50V), but 100uF caps used for converters shown above are rated 35V on schematic. I could not decode actual markings of those caps marked "100 HFT 9B1" that are actually mounted on board, I've tried to find them on the web but I was unsuccessful. Also ceramic caps are never marked on its case, so it is impossible to confirm their voltage rating.
@dc42 said in 32,4v input instead of 32v:
@mandragora if you look at the capacitors on your 6HC you may find that they are rated 50V.
Does that mean that this schematic differs from actually mounted components? If yes, are there more changes in different parts of the design? I tried but didn't find any BOM to confirm what is actually mounted.
Kind Regards,
@cosmowave Are those brass barbs custom or off the shelf?
I am also going to do something very similar in future.
You might also consider this kind of barbs:
https://www.aliexpress.com/item/10000328905489.html?spm=a2g0o.order_list.0.0.1eb11802NQgtOw
or:
https://www.aliexpress.com/item/10000328986062.html?spm=a2g0o.order_detail.0.0.540843ceOvlKPD
I've received those 2 weeks ago and seem pretty good quality.
Info in this thread was very useful and allows to increase voltage for better performance of stepper motors. I use 350W 24V supply (for heaters) with additional (modified with higher output capacitance) Boost converter to get around 37V for Duet3 6HC. Everything works fine.
@dc42 said in 32,4v input instead of 32v:
all components on the Duet 3 MB6HC are rated to at least 38V VIN max recommended and 40V absolute maximum.
I was checking other stuff on schematics and found that input capacitors of DC-DC converters are rated 35V max. So even considering input protection diode D3 absolute max input voltage is 35,5V. Correct me if I am wrong.
Kind Regards,
Ok, after successfully reinstalling firmware, I was able to connect to board with YAT via USB. After some debugging I created new configuration and web interface on new SD card - just to be sure (provided one was missing most of the files).
And BAM, DWC is present, now I can work from here.
Thanks for your reply.
I am not very familiar with this "software stuff" like gitlab etc. USB seemed easiest option since I don't have router around and my internet connection for computer is via Ethernet (so while connecting duet to laptop via Ethernet I don't have access to internet to look for help).
It seems that your solution worked:
Red DIAG LED is now flashing (1Hz)
Now I will connect duet to laptop via Ethernet to check if I can see web interface etc.
THX a lot for your help, I've spend 3h yesterday to figure out what was wrong.
Hello, I need some help/explanations too.
Just got myself a duet3, seller already provided SD with some files. I want to run it in standalone mode (no RPi).
I decided to upgrade firmware via USB as on guide: https://duet3d.dozuki.com/Wiki/Getting_Started_With_Duet_3#Section_Updating_Duet_3_main_board_firmware
Steps that I've followed:
Kind regards,