Managed to answer my own question.

Inverting the heater4 pin solved it.

Thanks

@dc42 sorry if I wasn't clear but that's exactly how I have it connected.

Thank you

@droftarts

I think what you really want is to set M143 to turn off the chamber heater when it gets to the set temperature.

Yes, this is exactly what i want to do and kind of what i figured was going on once i started setting my chamber temperature to 30C instead of 40C.

How do you set the chamber temperature currently?

Typically in the slicer

So what you said makes sense and was what I was going to test next, just lowering the S parameter value of M143.

Thank you for this info.

@OwenD
The Enclosure is made from an old medical refrigerator, double steel wall and insulted.

To be able to vent air, i need to open another hole in it to allow air in. I also need filtration since I only do ABS... Turns into more work than i want to do lol.

@deckingman
So what's the difference between M143 and M570 and how exactly do they coexist?
Like i set the max temp with M143 H2 S50 A1 followed by M570 H0 T100?

The GCode dictionary says the T parameter is for the allowed temperature excursion. Does that mean the max limit before a fault or the max of the allowable difference between the M143 setpoint and M570 T parameter? I just want to make sure I have it right

@OwenD
Thanks, this looks like the answer I was seeking. Had no idea about the system daemon but this is very useful. Ideally I want to shut the heater off once it hits the set temperature so I'm going to start exploring what's possible with this.

@deckingman
Thanks, I didn't know about M570.
My chamber heater is 120v running on an SSR, it was PID tuned but because my enclosure is so well insulated the temperature takes a loooooooong time to fall. This is part of the problem when printing because the bed heat doesn't allow the chamber temperature to fall at all. Once it reaches the set temp it never drops, only climbs.

Hello,

I have a custom cartesian printer in an insulated enclosure with a chamber heater. Duet wifi 2 and all electronics other than steppers are outside the enclosure. I've been running this setup for a while but in the last 6 months I've experienced the same odd behavior twice now.

Typically I set my chamber heater to 30-40C, because my enclosure is near air tight and double-wall insulated, once the set temperature is reached the heater doesn't need to turn on again. The enclosure will easily get to 50+ degrees or more after reaching the set temp.

Initial problem with this was the printer would halt due to the measured temperature exceeding the set temperature. I then configured this heater via M143 using the A1 parameter to turn the heater off permanently. This has worked fine for years.

Now, I've had it happen twice now where the print pauses and the head parks because of the fault. The first time I wasn't around when it happened, the second time was just now and i was beside the printer.

This is my heater config:

M950 H2 C"!exp.heater4" T2									; create chamber heater output on heater4 and map it to sensor 2
M307 H2 A170.0 C4590.7 D1.4 V24.4 B0 S1					; disable bang-bang mode for the chamber heater and set PWM limit
M141 H2													; map chamber to heater 2
M143 H2 S50 A1											; set temperature limit for heater to 50C, turn off once exceeded (A1)

I'm running FW version 3.4.6

Has anyone observed this before?

Edit, after re-reading this and looking at my config i think I know what is happening.
Previously i would set my chamber temp for 40C, it would hit 50C before there was any kind of fault I assume that is why A1 would turn it off.

What's happening now is i have my temp set for 30C and it doesn't reach 50 to shut itself off. So there is a general heating fault because my chamber is still climbing beyond the set temp but doesn't hit 50C in time.

Is there any workaround for this?

Thanks,

@dc42 sorry if I wasn't clear but that's exactly how I have it connected.

Thank you

Managed to answer my own question.

Inverting the heater4 pin solved it.

Thanks

Afternoon all,

I recently built another enclosure for my printer with a chamber heater.

Followed this guide:
https://duet3d.dozuki.com/Wiki/Connecting_and_configuring_a_chamber_heater

I have a duet 2 wifi running RRF 3.x
Chamber heater is 120VAC connected to a Crydom D2425, with SSR input connected to expansion connector pins 3(3.3v) and 13(Heater4)

This is the configuration code related to the chamber heater:

M308 S2 P"e1temp" Y"thermistor" T100000 B4725 C7.06e-8  ; configure sensor 2 as thermistor on pin e1temp
M950 H2 C"exp.heater4" T2				; create chamber heater output on heater4 and map it to sensor 2
M307 H2 B0 S1						; disable bang-bang mode for the chamber heater and set PWM limit
M141 H2							; map chamber to heater 2
M143 H2 S50						; set temperature limit for heater to 50C

I had used the thermistor input for e1 not realizing i could also use the e1 heater output to control the SSR that is why i used heater4.

It took a while before i figured out i had to add 'exp' to the M950 command. After i did the heater showed up properly in DWC with temperature readings. Problem is that it appears to be operating in reverse.

When the Duet boots, the SSR is activated so heater is on, even though the firmware reports it off. If i turn it on in DWC, the heater turns off until it enters fault because the temperature is not climbing.

I triple checked all connections, 3.3v pin is going to + input of the SSR and heater4 pin is going to the other. Reversing them makes nothing work at all. If i remove the heater configuration it does not activate on boot.

Any advice?

@dc42

As far as I can tell they do, and I've quadruple checked the linear rail alignment that the gantry moves freely up and down without binding.

The only other thing i can think of is that i also added anti-backlash lead screw nuts... They were generic off of amazon, maybe they're causing some kind of additional resistance.

I may end up disassembling/reassembling the whole thing and verifying all wiring as well because this is the first time I've been really stumped.

But after a few tests this morning the consistency seems more reliable with independent Z drives so I'm going to move onto the next problem.

Thanks,

@Phaedrux

Yeah i had caught that just after posting. Fixed it and all is good.

Preliminary testing using a feeler gauge is that the height movement is consistent, or at least more than it was before.

But I've been wondering. Prior to all my changes i ran 12V, with the original Anet A8 stepper motors, with the dual Z connected to Z1 and Z2 and never had this problem.

Is there something wrong with the new motors i bought? Should i be looking at just replacing the Z motors with something more suitable?

Thanks,

@Phaedrux said in inconsistent Z movement:

What is connected to drivers 2 and 4?

Originally Each Z motor was connected to Z1/Z2 (driver 2), i moved one to E1 (Driver 4) for each to be on their own driver as you suggested

@Phaedrux said in inconsistent Z movement:

Do you have the jumpers installed in the second Z port?

I didn't realize in the wiring diagram that there was option A and option B. After seeing that i installed the jumpers and now both motors are moving.

So now new issue. Home x and Home Y lift Z by a few mm. I can see one Z motor is spinning faster than the other because one coupler expands... I doubt this is config related, what could potentially cause this, bad wiring?

Edit, I just realized they're spinning in opposite directions
Edit 2: Fixed that with M569 for driver 4. Will continue to test