Duet2Wifi Using 3 Heaters for a extruder

mikep91

Hello there.

We recently got a hot-end with 3 heaters. Dyze Pulsar to be specific. Before we used a marlin board with 3 pinouts for the temperature sensors.
Now we upgraded to a Duet2Wifi with PT100 Daughterboards attached.
I connected the sensors to the PT100 daughtersboards but how would I go about connecting the heaters? They're connected through solid state relays to switch them on & off.

Should i use the small expansion pin (8, heater 3) or is it possible to use the Bed Heater as the 3rd one since we haven't got a heated bed?

; Heaters
M140 H-1 ; disable heated bed
M305 P1 X200 ; configure PT100 for heater 1
M143 H1 S500 ; set temperature limit for heater 1 to 500C
M305 P2 X201 ; configure PT100 for heater 2
M143 H2 S500 ; set temperature limit for heater 2 to 500C
M305 P3 X202 ; configure PT100 for heater 3
M143 H3 S500 ; set temperature limit for heater 3 to 500C

M570 H1 P30 T100 ; 100C overshoot for 30 sec permitted heater 1
M570 H2 P30 T100 ; 100C overshoot for 30 sec permitted heater 2
M570 H3 P30 T100 ; 100C overshoot for 30 sec permitted heater 3

; Tools
M563 P0 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
M563 P1 H2 F0 ; define tool 1
G10 P1 X0 Y0 Z0 ; set tool 1 axis offsets
G10 P1 R0 S0 ; set initial tool 1 active and standby temperatures to 0C
M563 P2 H3 F0 ; define tool 2
G10 P2 X0 Y0 Z0 ; set tool 2 axis offsets
G10 P2 R0 S0 ; set initial tool 2 active and standby temperatures to 0C

I understand that i could connect these in series but we would like to be able to control different temperatures in different areas of the hot-end. Therefor we would prefer to have them connected seperately from eachother.

All help appreciated!

dc42

@mikep91 you can use M563 to define a single tool that uses 3 heaters. You will need to use M568 or G10 (not M104 or M109) to set the temperatures if you want them to be different.

mikep91

@dc42

Not that familiar with g-code unfortunately. How would that look?
We set the temperature on the Duet Paneldue and not using G/M-codes

How would I go about wiring the 3rd heater to the Duet2Wifi board?

Only have two pinouts for E0 and E1, do I have to use the small pins on the expansion board? I think it's Pin8 thats stated as Heater3

Thanks!

Phaedrux

@mikep91 said in Duet2Wifi Using 3 Heaters for a extruder:

do I have to use the small pins on the expansion board? I think it's Pin8 thats stated as Heater3

Yes.

https://docs.duet3d.com/duet_boards/duet_2_wifi_ethernet_maestro/duet2ndgen_connections_v1.0-1.5_d2.1.png

mikep91

@phaedrux

So i hook up my the one connector to 5v (Pin1)
And the 2nd to HEATER3 (Pin8)?

Thanks!

dc42

@mikep91 said in Duet2Wifi Using 3 Heaters for a extruder:

Only have two pinouts for E0 and E1, do I have to use the small pins on the expansion board? I think it's Pin8 thats stated as Heater3

Yes, and then use a mosfet or SSR to control the heater from that pin, because those pins can only provide a small amount of current and only at 3.3V. DO NOT connect a heater directly to expansion pin 8.

kr15_uk

@mikep91 I’d personally suggest to go with Duex5 expansion board in your case.

deckingman

@mikep91 In another thread, a user with. Dyze hot end had great difficulty in tuning the PID parameters for the individual heaters because of the thermal transfer interaction between heaters. That is to say, there were no thermal breaks between the heat zones so effectively it had a single heat zone. The only way to tune the PID parameters was to wire the heaters in parallel to single heater output and use a single sensor. I.e treat it a single heater with a single sensor (they all read the same temperature within a degree in any case).

mikep91

@kr15_uk

I suppose I would need to configure new software? or does Duex and DUET2Wifi run the same?

Just checked out the board and it looks like what I need indeed

mikep91

@dc42 said in Duet2Wifi Using 3 Heaters for a extruder:

@mikep91 said in Duet2Wifi Using 3 Heaters for a extruder:

Only have two pinouts for E0 and E1, do I have to use the small pins on the expansion board? I think it's Pin8 thats stated as Heater3

Yes, and then use a mosfet or SSR to control the heater from that pin, because those pins can only provide a small amount of current and only at 3.3V. DO NOT connect a heater directly to expansion pin 8.

Thanks for the help so far.

I've connected my two wires to Pin8 and Ground
They're all 3 connected to solid state relays

It seems 3rd heater is faulty somehow. When i set the temperature to 200 on all heaters, the 3rd one just keeps heating.
OBS; Without im activating the heater on on the Duet Touch Panel,
Could it be that i switched some wiring, or do I have to look in the config perhaps?

kr15_uk

@mikep91 If you are using web config toot (https://configtool.reprapfirmware.org) then under I/O Mapping tab there are two buttons "Add Duex2" and "Add Duex5" which then adds expansion ports as an option to chose from the drop down menus.

mikep91

@kr15_uk

I am not creating a new software unfortunately im using the Config. file on my current board

kr15_uk

@mikep91 You can load existing profile and amend it there.

mikep91

@kr15_uk

Ah nice. I'll take a look at it.

I don't have an IDEX Board though and if possible i would just like to connect it using the Duet2Wifi.

It seems im lacking something to make it work properly though, maybe a 3rd heater config in my code...

kr15_uk

@mikep91 if you suspect external circuitry to be at fault here you could simply uncomment bed and use bed mosfet to drive 3rd heater

mikep91

@kr15_uk

Nice thats actually what i did for a start.

I figured out how to use the expansion pins though and it works like a charm!
Thanks for the help and support!

Will def go for a IDEX board next time we're upgrading