"auto tune cancelled because target temp not reached" problem
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I updated to RRF 1.18 this morning on one of my machines. I believe I made a print with the E3D V6 (24V) hot end originally on this machine. I just swapped over to a new E3D Titan Aero (24V) to test and immediately had issues trying to reach my set point 190°C. I assumed that it has the same cartridge heater the V6 has and didn't attempt to tune.
So I went down the path to auto tune and read the wiki and searched here. Issuing an M303 H1 S240 I get this return string:
"Auto tuning heater 1 using target temperature 240.0C and PWM 1.00 - do not leave printer unattended"
and the temp starts rising very slowly. Then after a ~5min or so with the temp at around 120°C autotune fails with:
"Auto tune cancelled because target temperature was not reached"
I've searched the wiki and forum and do not see this problem described. Help greatly appreciated!
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And this is M307 for the hot end:
M307 H1
Heater 1 model: gain 340.0, time constant 140.0, dead time 5.5, max PWM 1.00, mode: PID
Computed PID parameters for setpoint change: P13.4, I0.095, D51.4
Computed PID parameters for load change: P13.4, I0.949, D51.4 -
The error message means exactly what it says. Looks like you either have a wiring issue that is preventing the full 24V getting to your hot end heater, or you have a faulty hot end heater. What is the resistance of the heater, measured from where the wires go into the terminal block on the Duet?
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Thanks David, I measure 20.5 ohms
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I just swapped over to my E3D V6 that was on this machine before. Set to 190°C and it worked perfectly getting to the set point. I did not re-run PID autotune on this one yet, I'll do that as soon as it cools off.
This verifies the wiring to the connector I plug the hot end cartridge in to is fine. It could be a bad crimp on the Titan Aero connector that I installed perhaps.
Update: Hmm, the crimps look great and seat properly in the connector.
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20.5 ohms works out as 28W @ 24V, which should be enough unless a fan is blowing a lot of cool air over the heater block.
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The stock Titan Aero fan is big but not directed anywhere near the heater.
I am running PID auto tune on the original V6 now and it behaves much differently/better. Rose up to 240°C relatively quickly with peak at 240.6°C. Now in auto tune phase 3.
Once this is done I'll reattach the Aero and check everything again. Both my Aero and the V6 have the "blue wire" 30W 24V cartridge heaters. It's what E3D send stock for 24V cartridges.
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I got the "warning Heater 1 appears to be over powered and a fire risk" message but the V6 tuned fine. I know how to deal with the warning.
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Nope, the Aero failed again at 121°C. This time I unplugged the cooling fan just to be sure. The heater block also has the silicone sock on it. I have spare cartridges but I really don't think that's the issue unless you think it's worth trying.
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Ok, I increased the dead time to 30s and again, auto tune cancels at 123°C. Can you recommend anything? I think I might pull the cartridge out of the V6 and put it in the Aero and be done with it for now.
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I swapped cartridges and the Aero heats up and auto tunes just fine. So there is either an issue with the new cartridge or the connector I crimped (although it looks fine). I'll redo the connector and try again later after I do some prints. Odd problem this one.
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A gent on the UltiBots D300VS group just got his kit yesterday and is having the exact issue that I saw with his hot end. He measured is resistance as 20.5 ohms as well and he's running RRF 1.15b - which is what the kit's Duet Wifi ships with.
I have a new V6 that came in a new D300VS kit I got last week to use for photographing for the assembly manual. I'm going to take a look tomorrow to see if that cartridge exhibits the same oddness.
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I can't PID tune my Aero either. I don't particularly care for how quick RRF cancels the tune just because it goes over temp by .1 degree. Usually in tuning it goes over I thought to know what value's to change to not overshoot the temp by too much.
This is also a 24v Aero, I don't know if the crappy meter I have is good enough to test the resistance and I Will check that tomorrow but my crimps are all solid on both ends.
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I can't PID tune my Aero either. I don't particularly care for how quick RRF cancels the tune just because it goes over temp by .1 degree. Usually in tuning it goes over I thought to know what value's to change to not overshoot the temp by too much.
It's changed in version 1.18, you set a target temperature and normally leave the PWM at 1.0.
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Reading this it seems likely that e3d have shipped a batch (at least 2) of duff heater cartridges.
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I can't PID tune my Aero either. I don't particularly care for how quick RRF cancels the tune just because it goes over temp by .1 degree. Usually in tuning it goes over I thought to know what value's to change to not overshoot the temp by too much.
It's changed in version 1.18, you set a target temperature and normally leave the PWM at 1.0.
Okie. I will give that a shot later, I am currently printing something to test everything. For now everything seems to be working but I have the heated bed on Bang Bang and it over shoots the temp by like 9 degrees. No idea why, my other Kossel doesn't do that.
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For now everything seems to be working but I have the heated bed on Bang Bang and it over shoots the temp by like 9 degrees. No idea why, my other Kossel doesn't do that.
That suggests that the thermistor is not in good thermal contact with the bed plate. Switching to PID may help, but even if you do then it would be better if you can improve the thermal contact.
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David, I'm reasonably convinced I have a bad cartridge. Two other 24V 30W cartridges work perfectly but this one does not. I can even tell that something is not quite right because it seems to "take off" slow and raises temp very slowly.
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Some more data, I received 3 hot ends directly from E3D this week to test. They all have 30W 24V heater cartridges. I measured the resistance of each:
Aero that led to this post: 20.5 ohms (28W)
2nd heater: 19.5 ohms (29.5W)
3rd heater: 19.2 ohms (30W)According to E3D docs, all are within +/- 5W spec. I have not tested the other two yet.
If I put the "defective" cartridge in my V6 that I swapped the cartridge out of and use the PID tuning I had done for it - which should be in the ballpark - the Aero cartridge raises temp from RT very slowly as previously observed and then errors out at around 118deg C.
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Do you have silicone socks on your heater blocks? They make a big difference to the heater power you need.
