Duex PWN pins gives 2.5 V and not 5 V

hsverre

I have a Duet Wifi and a Duex5 connected. Im trying to use one of the PWN1-5 connectors. The connector only gives 2.5 V and not the 5 V it should. I dont understand why? Can i use another 5 V pin to get 5 V power? What component on the Duex adapts the 5 V. I gues I have to measure it.

dc42

@hsverre the 5V supply to the DueX normally comes from the Duet through the ribbon cable. Recent DueX5 boards have a 5V AUX jumper allowing it to be switched to external 5V. So I suggest you check that jumper is in the correct position. See https://docs.duet3d.com/duet_boards/duet_2_expansion/duex_wiring_v0.11_d1.0.png.

hsverre

@dc42

It is in the correct position between 5V INT and 5V AUX and it gives 2.5 V. When I reomve the jumper it gives 0 V. I guess there has to be a hardware fault somewhere.

hsverre

@dc42
I guess there is a stepdownconverter somewhere. Might be a idea to measure it.

droftarts

@hsverre the PWM pins are Pulse Width Modulation pins, ie they pulse 5V at whatever interval you set. The voltage can be difficult to measure with a voltmeter at anything less 100% duty cycle, which needs to be set. So how have you set it up? Are you just plugging something in, expecting 5V? Please post your config.g and firmware version.

Ian

droftarts

@hsverre also note you can’t use the same heater and PWM pin on the DueX; heater E2 is shared PWM1, heater E3 is shared with PWM2, etc.

Ian

hsverre

@droftarts said in Duex PWN pins gives 2.5 V and not 5 V:

@hsverre Please post your config.g and firmware version.

Ian

Here it is:

RepRapFirmware for Duet 2 WiFi/Ethernet version 3.3 (2021-06-15 21:44:54) running on Duet WiFi 1.02 or later + DueX5

; Configuration file for Duet WiFi (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.2.3 on Fri Jul 30 2021 22:46:27 GMT+0200 (sentraleuropeisk sommertid)

; General preferences
G90 ; send absolute coordinates...
M83 ; ...but relative extruder moves
M550 P"Voron24" ; set printer name
M669 K1 ; select CoreXY mode

; Network
M552 S1 ; enable network
M586 P0 S1 ; enable HTTP
M586 P1 S0 ; disable FTP
M586 P2 S0 ; disable Telnet

; Drives
M569 P1 S0 ; z drive 1
M569 P2 S1 ; z drive 2
M569 P3 S0 ; z drive 3
M569 P4 S1 ; z drive 4
M569 P5 S1 ; a drive 5
M569 P6 S1 ; b drive 6
M569 P7 S0 ; ex drive 7
M572 P7 S0.19
M584 X5 Y6 Z1:2:3:4 E7
M671 X815:815:-125:-125 Y500:-130:-130:500 S20 ; leadscrews at rear left, front middle and rear right
M350 X16 Y16 Z16 E16 I1 ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z400.00 E419.19 ; set steps per mm
;M566 X900.00 Y900.00 Z60.00 E120.00 ; set maximum instantaneous speed changes (mm/min)
;M203 X6000.00 Y6000.00 Z180.00 E1200.00 ; set maximum speeds (mm/min)
;M201 X500.00 Y500.00 Z20.00 E250.00 ; set accelerations (mm/s^2)
M906 X800 Y800 Z800 E800 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

M98 P"/macros/print_scripts/speed_printing.g"

;M955 P0 C"spi.cs4+spi.cs3"

; Axis Limits
M208 X0 Y0 Z0 S1 ; set axis minima
M208 X787 Y452 Z500 S0 ; set axis maxima

; Endstops
M574 X1 S1 P"xstop" ; configure active-high endstop for low end on X via pin xstop
M574 Y1 S1 P"ystop" ; configure active-high endstop for low end on Y via pin ystop
M574 Z1 S2 ; configure Z-probe endstop for low end on Z

;BLTouch - Heaters
;M307 H2 A-1 C-1 D-1 ; Disable the 2. Heater to free up PWM channel 1 om the Duex board

;BLTouch
;M558 P9 C"^zprobe.in" H5 F120 T6000
;M950 S0 C"duex.pwm2" ; Duet 2 WiFi/Ethernet + DueX2/5
;G31 X20 Y0 Z0 P25

; Z-Probe
M950 S0 C"duex.pwm1" ; create servo pin 0 for BLTouch
M558 P9 C"^zprobe.in" H5 F120 T6000 ; set Z probe type to bltouch and the dive height + speeds
G31 P500 X0 Y0 Z2.5 ; set Z probe trigger value, offset and trigger height
;M557 X15:700 Y15:400 S80 ; define mesh grid;

; Z-Probe
;M558 P1 C"zprobe.in" H20 F6000 T6000 ; set Z probe type to unmodulated and the dive height + speeds
;M558 P9 C"^zprobe.in" H5 F120 T6000 ; set Z probe type to unmodulated and the dive height + speeds

;G31 P1000 X0 Y0 Z1.862 ; set Z probe trigger value, offset and trigger height

M557 X15:780 Y15:450 S30 ; define mesh grid

; Heaters

M308 S0 P"bedtemp" Y"thermistor" T50000 B4138 ; configure sensor 0 as thermistor on pin bedtemp
M950 H0 C"bedheat" T0 ; create bed heater output on bedheat and map it to sensor 0
M307 H0 B0 R0.297 C322.9 D14.09 S1.00 V12.4
;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"e0temp" Y"thermistor" T100000 B4725 C7.06e-8 ; configure sensor 1 as thermistor on pin e0temp
M950 H1 C"e0heat" T1 ; create nozzle heater output on e0heat and map it to sensor 1
M307 H1 B0 R2.485 C220.4 D6.96 S1.00 V12.2
;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"fan0" Q500 ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"fan1" Q500 ; create fan 1 on pin fan1 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

hsverre

@droftarts said in Duex PWN pins gives 2.5 V and not 5 V:

@hsverre also note you can’t use the same heater and PWM pin on the DueX; heater E2 is shared PWM1, heater E3 is shared with PWM2, etc.

Ian

I use non of the Duex heaters.

droftarts

@hsverre What are you trying to connect, and to where? You have a BLTouch connected to PWM1. The PWM pin is to control the BLTouch deployment, not supply 5V to it.

Ian

hsverre

@droftarts said in Duex PWN pins gives 2.5 V and not 5 V:

@hsverre What are you trying to connect, and to where? You have a BLTouch connected to PWM1.
The PWM pin is to control the BLTouch deployment, not supply 5V to it.

Ian

Yes I have a BLTouch at PWM1 and it does not work. Not action what so ever. And it works fine on another printer.

So this pins are not supposed to give 5V? Between GND and 5V AUX as the duex schematics show?

If so i guess the BLTouch get power from the Probe pins on the Duet Wifi then?

dc42

@hsverre yes you can power a BLTouch from the 5V_AUX pin on the DueX.

If you have a multimeter then you could trace the path of the 5V rail. There should be 5V on pin 1 of the expansion connector on the Duet, then 5V on pin 1 of the expansion connector on the DueX, then 5V on the 5V_AUX jumper of the DueX. Take care not to short 5V to ground when measuring it.

droftarts

@hsverre You have another thread going with the same issue: https://forum.duet3d.com/topic/27279/bltouch-not-working/24
Please don't start a second thread. You'll just be asked the same questions all over again.
And yes, 5V AUX should supply 5V. Follow the troubleshooting @dc42 suggested to trace the 5V rail.

Ian

hsverre

@droftarts said in Duex PWN pins gives 2.5 V and not 5 V:

@hsverre You have another thread going with the same issue: https://forum.duet3d.com/topic/27279/bltouch-not-working/24
Please don't start a second thread. You'll just be asked the same questions all over again.
And yes, 5V AUX should supply 5V. Follow the troubleshooting @dc42 suggested to trace the 5V rail.

Ian

Yes the other thread is about the BLTouch, this one is about the PWM and how it works.

Im sorry if I did a mistake. Can i take any actions to make it ok again?

Of course the tracing seems like a proper next step. Ill be back

hsverre

@dc42 said in Duex PWN pins gives 2.5 V and not 5 V:

@hsverre yes you can power a BLTouch from the 5V_AUX pin on the DueX.

If you have a multimeter then you could trace the path of the 5V rail. There should be 5V on pin 1 of the expansion connector on the Duet, then 5V on pin 1 of the expansion connector on the DueX, then 5V on the 5V_AUX jumper of the DueX. Take care not to short 5V to ground when measuring it.

I used a multimeter (without shortcutting ) to measure. The 5V on pin 1 on the expanasjon connector at the Duet reports 5V, the pin 1 on the expansion connector on the Duex reports 2.5-ish V (BTW the 3.3 V pin reports 3.3 V) and the 5V_AUX reports 2.5-ish V.

hsverre

Where did everyone go? Did i say something wrong? What happened?

JoergS5

@hsverre I would try to help, but don't understand it.

You meant pin 1 on Duet is 5 V, but pin1 on Duex 5 is 2.5 V? They are directly connected by gray cable? Ony reason could be that the grounds are not connected. (Ground of Duet and ground of Duex). At
https://duet3d.dozuki.com/Wiki/Duex2_and_Duex5_Features#Section_Wiring
are some comments on connecting grounds.

If this is not the reason, please make some images of the wiring and where you measured. And information about the Duex release. And how you set the jumpers.

hsverre

@joergs5

Hurray. I finally found out that the problem was the gray fat ribbon cable between the Duet and the Duex. God knows why. It could be that the grounding is the problem then.

Thanks a lot for all the replies

JoergS5

@hsverre thanks for information, I am glad that you found the reason. Happy printing