PID tunin - Temp too high
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@tom33 do you get that error when you command the hot end to heat to 205C from cold? If so then try reducing the R parameter in the M307 command. Try a 20% reduction.
You are correct to delete the second M307 H1 command. That would have overridden the first one.
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@dc42 Yes but even if I order to heat when the temperature is at 150°C for exemple.
I already try this. I reduce up to 50% with no impact...
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@tom33 said in PID tunin - Temp too high:
I already try this. I reduce up to 50% with no impact...
Do you also have a config-override.g file?
Can you please share your complete config.g and config-override.g if it exists? -
@phaedrux
I delete the config override, I'll try tomorrow and send the results -
Warning: Turning on the print cooling fan did not increase hot end cooling. Check that the correct fan has been configured.
Auto tuning heater 1 completed after 3 idle and 10 tuning cycles in 1505 seconds. This heater needs the following M307 command:
M307 H1 B0 R1.829 C407.7:407.7 D20.33 S1.00 V24.0
Send M500 to save this command in config-override.gI have the following message after PID tuning, I reduce de R value by 20% and still the same problem
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Can you post a photo of your hotend assembly?
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Are the hotends in contact at all? Are both heated when you tune? Could they be affecting each other?
Can you share your full config.g please?
Warning: Turning on the print cooling fan did not increase hot end cooling. Makes sense as you don't appear to have a part cooling fan in the photo.
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@phaedrux I restart a PID tuning without layer fan in the config.g I will tell you the results. Also I'm using a SSR relay for the heater cartridge could this be the problem ?
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@phaedrux same problem with fan off and R value decrease by 20%
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@tom33 please try heating the hot end in stages, first to 100C, then to 160C and finally to 205C. If that works, when the temperature had settled run M573 P1 periodically, wait until the result has settled, then report it here. That will give me a better idea of what is going on.
I was wrong to suggest you reduce R to correct the overshoot, it's the other way round. So try increasing R by 30%.
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@tom33 the temperature oscillations suggest that the dead time measurement wasn't accurate either. Try increasing the M307 D parameter by about 20% at a time until the oscillations stop. You should be able to do this while the hot end is up to temperature, just send M307 H1 Dnnn.
Is this a commercial hot end, or one you designed?
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@dc42 This is a dyze hotend, I will try this tomorrow morning
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@dc42 much more better by increasing the D parameters but still the same problem with the overshoot (+20°C of the target)
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@tom33 now try increasing the R parameter to eliminate the overshoot.
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@dc42 same problem. When I look at the led on the board, the heating stop only when the target value is reached, there is no anticipation.
The last solution is to calculate the PID value and set by M303 ?
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@tom33 said in PID tunin - Temp too high:
@dc42 same problem. When I look at the led on the board, the heating stop only when the target value is reached, there is no anticipation.
I'm sorry, I assumed that graph you posted was from normal operation of the hot end. If it is from tuning, then it is normal. During tuning, the heat remains on until the target temperature is reached, so there will always be an overshoot.
My advice to increase the D parameter was on the assumption that you were getting temperature ripples during normal use of the hot end. Ripples during tuning are normal.
If the overshoot during tuning is a big problem, then either tune at a lower temperature (M303 T parameter), or at a lower PWM (M303 S parameter).
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@dc4 The graph is not from tuning operation. I target 160 and after 205 °C
I will try this, I'm using a SSR relay for my heater cartridge, the overshoot problem can it cause by the relay ?
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@tom33 overshoot can be hard to control if the heater is over-powered. However, if you have stopped the oscillations by increasing the dead time, then I think it should be possible to stop the overshoot by increasing the R parameter.