@Phaedrux unfortunately there is a media embargo on the specifics of the project currently, but we will undoubtedly share more news when permitted!

@Phaedrux this is part of a grant-funded feasibility study for a new technology that is being developed. It requires 6 Nema 23 motors (about which I believe you assisted with my other question on power supply sizing) to run synchronously on a global radial hub with stall detection and reasonably high current per driver. The Duet 3 is capable of this and is really good value compared to alternatives, and I have been an avid proponent of the Duet series for a number of years in most applications that require stepper control. I would rather have all drivers on one axis to avoid a situation where, most likely by accident, motors are working against others that are in a locked state, which could damage the mechanism.

@dc42 Though I'm sure its low on any of your to-do lists, it would be greatly appreciated if you could increase the max to 6 in a future update!

@deckingman Thank you for the suggestion. If I add the line as suggested then the U axis doesnt even show up on DWC, and sending a G1 U** move doesnt work. However, if I remove any one of the drives from the list for the U axis(i.e 0.0) then it does show up, and runs the assigned five motors as before. The X,Y,Z moves work as normal as you said, do you think its fair to assume this is a firmware flaw of some sort? Thanks again.

I have just set up a Duet 3 6HC in standalone mode with 6 Nema 23 steppers. I want to assign all 6 on board drivers to a single axis (I have been attempting to use the X axis but Im not concerned which I use). When I use M584 in my config file, if I assign drivers 0.0 to 0.5 to the X axis, only 0.0 runs when I prompt a move in the X axis. If I assign 0.1 to 0.5 to X, all drivers run except for 0.0. Am I missing something that is required, is it necessary to assign a driver to each axis or something similar? I have appended my config file for reference. Thanks in advance for any help.

; Configuration file for Duet 3 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.1.4 on Tue Oct 27 2020 14:34:47 GMT+0000 (Greenwich Mean Time)

; General preferences
G90 ; send absolute coordinates...
M83 ; ...but relative extruder moves
M550 P"Project SL" ; set printer name

; Network
M552 P192.168.1.11 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
M569 P0.1 S1 ; physical drive 0.1 goes forwards
M569 P0.2 S1 ; physical drive 0.2 goes forwards
M569 P0.3 S1 ; physical drive 0.3 goes forwards
M569 P0.4 S1 ; physical drive 0.4 goes forwards
M569 P0.5 S1 ; physical drive 0.5 goes forwards
M584 X0.1:0.2:0.3:0.4:0.5 ; set drive mapping
M350 X16 I1 ; configure microstepping with interpolation
M92 X80.00 ; set steps per mm
M566 X900.00 ; set maximum instantaneous speed changes (mm/min)
M203 X6000.00 ; set maximum speeds (mm/min)
M201 X500.00 ; set accelerations (mm/s^2)
M906 X700 Y700 Z700 E700:700:700 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Axis Limits
M208 X0 Y0 Z0 S1 ; set axis minima
M208 X230 Y210 Z200 S0 ; set axis maxima

; Endstops
M574 X1 S1 ;

; Z-Probe
M558 P0 H5 F120 T6000 ; disable Z probe but set dive height, probe speed and travel speed
M557 X15:215 Y15:195 S20 ; define mesh grid

; Fans
M950 F0 C"out3" Q500 ; create fan 0 on pin out3 and set its frequency
M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"out4" Q500 ; create fan 1 on pin out4 and set its frequency
M106 P1 S1 H1 T45 ; set fan 1 value. Thermostatic control is turned on

; 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

That's brilliant, thanks again for your help. I found the voltage from digging around the model number but certainly seems it wasn't for the right thing. I'll get a smaller power supply than planned and be very grateful for saving a few quid.

I shall take note of that! The next day delivery was too tempting at the time. Here is the listing for the motors Ive purchased:

https://www.amazon.co.uk/gp/product/B07QN1YX98/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Thanks for your responses, I plan to use a 24V power supply as it is compatible with some external (low power) peripherals I need to use. The motors as far as I can tell are rated 12V, but the listing (Amazon) doesnt offer a great deal of detail so I cant be certain. The details listed are
Step Angle 1.8°
Rated Current 2.8A
Holding Torque 1.3Nm
Phase Resistance 1.0Ohm
Phase Inductance 2.1mH
Rotor Inertia 460g.cm²
Shaft Diameter: 6.35mm
Motor Body Length 76mm

Hi, I did read this, unfortunately the numbers I get out from the rated current squared and the current x voltage on the motors Ive got are very different (which I realise is just the suppliers mistake), so I wanted to get a picture of what would typically be expected for these sized motors before committing to an under/over sized supply.

I am sizing the required power supply for a setup having just purchased a Duet 3. I am looking to run 6 Nema 23 (1.3Nm, 2.8A, 1Ohm Resistance) steppers synchronously at 24V. My understanding is that the motors will require ~30W each, so about a 200W supply, but would appreciate any advice. I will be running the motors at a max of 200rpm. Apologies, Im sure this topic is answered previously on the forum but I have not been able to find it. Thanks in advance!