M950 with Expansion Boards, odd config required on part coolers

PDBeal

So I noticed a strange issue with my Part Cooler Fans that are all connected to the Duet3 3HC Expansion boards. All of my part coolers are connected to 1.out3/1.out4/2.out3/2.out4 respectively and are all plain 2-wire 24V DC 5015 Blower (technically 2 identical blowers on a y-cable) The blowers are specifically https://www.digikey.com/en/products/detail/mechatronics-fan-group/B5015E24B-BSR/5209731, and I have 8 of them with 2 per tool head.

And for some detail, the relevant sections of my config.g file:

; Tool 0 (Autotune - M303 T0 S275)
M950 H1 C"1.out0" T1                ; create heater #1
M143 H1 P0 T1 C0 S300 A0            ; configure heater monitor #1 for heater #1
M307 H1 R3.284 K0.589:0.183 D1.93 E1.35 S1.00 B0 V24.2  ; from pid tuning

; Tool 0 Fans
M950 F0 C"1.out6"                     ; create fan #0
M106 P0 S255 H1 T45 C"HotendFan0"     ; configure fan #0
M950 F1 C"1.out3" Q10000              ; create fan #1
M106 P1 S0 H-1 C"PartCooler0"         ; configure fan #1

; Tool 1 (Autotune - M303 T1 S275)
M950 H2 C"1.out1" T2                ; create heater #2
M143 H2 P0 T2 C0 S300 A0            ; configure heater monitor #2 for heater #2
M307 H2 R3.714 K0.459:0.277 D1.82 E1.35 S1.00 B0 V24.2  ; from pid tuning

; Tool 1 Fans
M950 F2 C"1.out7"                     ; create fan #2
M106 P2 S255 H2 T45 C"HotendFan1"     ; configure fan #2
M950 F3 C"1.out4" Q25000              ; create fan #3
M106 P3 S0 H-1 C"PartCooler1"         ; configure fan #3

; Tool 2 (Autotune - M303 T2 S275)
M950 H3 C"2.out0" T3                ; create heater #3
M143 H3 P0 T3 C0 S300 A0            ; configure heater monitor #3 for heater #3
M307 H3 R3.458 K0.551:0.199 D1.96 E1.35 S1.00 B0 V24.2  ; from pid tuning

; Tool 2 Fans
M950 F4 C"2.out6"                     ; create fan #4
M106 P4 S255 H3 T45 C"HotendFan2"     ; configure fan #4
M950 F5 C"2.out3" Q25000              ; create fan #5
M106 P5 S0 H-1 C"PartCooler2"         ; configure fan #5

; Tool 3 (Autotune - M303 T3 S275)
M950 H4 C"2.out1" T4                ; create heater #4
M143 H4 P0 T4 C0 S300 A0            ; configure heater monitor #4 for heater #4
M307 H4 R3.209 K0.533:0.229 D1.99 E1.35 S1.00 B0 V24.2  ; from pid tuning

; Tool 3 Fans
M950 F6 C"2.out7"                     ; create fan #6
M106 P6 S255 H4 T45 C"HotendFan3"     ; configure fan #6
M950 F7 C"2.out4" Q25000              ; create fan #7
M106 P7 S0 H-1 C"PartCooler3"         ; configure fan #7


; Tool definitions
;-------------------------------------------------------------------------------
M563 P0 S"Tool 0" D0 H1 F1
M563 P1 S"Tool 1" D1 H2 F3
M563 P2 S"Tool 2" D2 H3 F5
M563 P3 S"Tool 3" D3 H4 F7

G10  P0 S0 R0               ; Set tool 0 operating and standby temperatures
G10  P1 S0 R0               ; Set tool 1 operating and standby temperatures
G10  P2 S0 R0               ; Set tool 2 operating and standby temperatures
G10  P3 S0 R0               ; Set tool 3 operating and standby temperatures

; Filament Sensor
M591 D0 P1 C"1.io0.in" S0   ; Simple filament sensor on toolboard 1 in0, disabled, output low when no filament
M591 D1 P1 C"1.io1.in" S0   ; Simple filament sensor on toolboard 1 in1, disabled, output low when no filament
M591 D2 P1 C"2.io0.in" S0   ; Simple filament sensor on toolboard 2 in0, disabled, output low when no filament
M591 D3 P1 C"2.io1.in" S0   ; Simple filament sensor on toolboard 2 in2, disabled, output low when no filament

The blowers that are connected to 1.out3 work with M950 using Q10000, but the other blowers connected to 1.out4 and 2.out3 and 2.out4 all needed Q25000. If I used Q10000 across all the PartCoolers, they would not run at 5% and only started blowing at 40% except the blowers connected to 1.out3 would run at 1% with Q10000. I had to change 1.out4, 2.out3, and 2.out4 to use Q25000 before the behaviors matched the blower connected to 1.out3 (I did try Q15000, but it didn't push the same amount of air until it was at Q25000 against my un-calibrated hand)

It also doesn't seem to matter which blowers I plugged into 1.out3. They would operate without issue with Q10000 and actually pushed too much air if it ran at Q25000.

I have my setup working, but with this weird difference on 1.out3 compared to the other outputs I figured I should at least report it incase there is a bug in the firmware that is causing this. Or if I have something odd in my blower configuration that's causing this I'd like to know also. I can also upload the entire config if necessary.

The Mainboard is a Duet3 6HC with SBC and (2) Duet3 3HC expansion boards on CAN1 and CAN2. All are running 3.5.1 firmware files with 3.5.1 DWC.

droftarts

@PDBeal Would it be possible to get an oscilloscope trace on 1.out3, and for comparison one of the others, to see what frequency it is actually outputting? I can only think there is some component failure that's doubling the frequency, or something similar.

Ian

PDBeal

@droftarts
I can try put my Flea-Scope on it and see if it can see any differences.

Although, with all of these boards being brand new and only in operation a week or so, I wouldn't expect it to have a failed part already unless defective from the start.