Heating fault on hot end
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@itsthejoker I still need to see the contents of your config-override.g. You posted config-user.g which seems to something specific to Railcore users. At the end of your config.g file you have M98 P"config-user.g" which will load that file and overwrite some of the commands in your config.g. But then you you have M501 which will load config-override.g and as it's name implies, any commands in there will override anything in both config.g and config-user.g. I haven't yet seen anything in your configuration files which reflect the result of the PID tuning you did - that's why I need to see what's in config-override.g.
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I've just noticed that you are running a very old version of firmware from 2020. There have been a lot of changes to the heater tuning algorithm since then. Might be worth upgrading (although coming from 2.05 is quite a lot of work).
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@deckingman Oh crap, I'm sorry, reading comprehension failure on my part. Config override attached:
; config-override.g file generated in response to M500 at 2023-07-02 02:14 ; This is a system-generated file - do not edit ; Heater model parameters M307 H0 A304.4 C773.3 D9.3 S1.00 V24.1 B0 M307 H1 A812.0 C265.2 D0.6 S1.00 V24.2 B0 M307 H2 A340.0 C140.0 D5.5 S1.00 V0.0 B0 M307 H4 A340.0 C140.0 D5.5 S1.00 V0.0 B0 M307 H5 A340.0 C140.0 D5.5 S1.00 V0.0 B0 M307 H6 A340.0 C140.0 D5.5 S1.00 V0.0 B0 M307 H7 A340.0 C140.0 D5.5 S1.00 V0.0 B0 G10 L2 P1 X0.00 Y0.00 Z0.00 G10 L2 P2 X0.00 Y0.00 Z0.00 G10 L2 P3 X0.00 Y0.00 Z0.00 G10 L2 P4 X0.00 Y0.00 Z0.00 G10 L2 P5 X0.00 Y0.00 Z0.00 G10 L2 P6 X0.00 Y0.00 Z0.00 G10 L2 P7 X0.00 Y0.00 Z0.00 G10 L2 P8 X0.00 Y0.00 Z0.00 G10 L2 P9 X0.00 Y0.00 Z0.00 -
@deckingman I just finished replacing the cable with a custom one and it makes it all the way to 220 in one go now and doesn't trigger the heater fault -- haven't changed anything else. Running a PID tune now, then will post the M307 results from the tune. Maybe this is just cable 'going bad' as opposed to breaking entirely. Two in a row though is weird.
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M307 H1 Heater 1 model: gain 853.7, time constant 199.1, dead time 1.6, max PWM 1.00, calibration voltage 24.2, mode PID, inverted no, frequency default Computed PID parameters for setpoint change: P25.8, I1.443, D29.1 Computed PID parameters for load change: P25.
and now it's rock solid. I'm so confused. Guess it's test print time?
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I actually wrote a long rambling post on heater and thermistor cables and the fun you can have with either poor connector contacts and also poor crimp joints. After writing the story and my examples I decide to not post it because the temperature graph you posted did not support my theory of what you were seeing.
I have seen more trouble with heater and sensor cables (and intermittent thermocouples) than any other failures short of operator failures. I have gone to PT1000 sensor for a lot of my temperature sensing needs. -
Test print went perfectly. I'll run another longer one, and if that works I'll look at updating the firmware (though I definitely don't want to lol).
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@itsthejoker I'm by no means any sort of expert on the process of tuning the PID parameters but I have a gut feeling that it can be an iterative process - especially with powerful heaters such as yours. It seems to me that it can take a few attempts with each attempt giving somewhat better control than the last. I don't know that for sure so no doubt someone will shoot me down in flames if I'm wrong. It's a gut feeing I have although based on empirical evidence. In your case, you can see the difference in time constant between success tuning cycles. Maybe it's just coincidental or maybe it takes some time for the heater itself to "settle down".
With a powerful heater you have a very high gain, so it's more likely to overshoot the set temperature. This tendency to overshoot needs to be "tamed" but if it's tamed too much, then you can end up with too slow a rise time which is what you were seeing at first. I have a feeling that, now that you have a PID model that works, you won't have any more problems.
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@deckingman we're in the same boat then; everything seems to be happy now with the latest wire change, so I suppose I'll keep an eye on it and see what happens? The current temperatures look great and totally expected (with the exception of the mild curve on the rise):
Thanks a lot for taking a look and I'm sorry this isn't a more satisfying ending lol -
@itsthejoker The main thing is that your issue seems to be fixed - despite the fact that we're not 100% sure why (I still think it's just that the tuning cycle needs to be repeated a few times, especially with high powered heaters).
