Chamber heater, how to disable "temperature rising too slowly"?
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Is it possible to completely disable the chamber heating monitoring feature that spits out ""temperature rising too slowly" fault?
In my setup I have AC 500W heater with dedicated circuitry to control fan speed that blows exactly 70C air.
I use fan2 output to turn heater ON/OFF with SSR and 24V fan.config.g
M308 S0 P"bedtemp" Y"thermistor" T102000 B4300 R4700 A"BedHeat" ; configure sensor 0 as thermistor on pin bedtemp
M308 S1 P"e0temp" Y"thermistor" T114000 B4300 R4700 A"Extruder" ; configure sensor 1 as thermistor on pin e0temp
M308 S2 P"e1temp" Y"thermistor" T100000 B4138 R4700 A"Chamber" ; Chamber Thermistor
M950 H0 C"bedheat" T0 ; create bed heater output on bedheat and map it to sensor 0
M950 H1 C"e0heat" T1 ; create nozzle heater output on e0heat and map it to sensor 1
M950 H2 C"fan2" T2 ; create chamber heater on fan2 and map it to sensor 2
M307 H1 B0 S1.00
M307 H1 A454.9 C173.2 D5.5 S1.00 V25.2 ; disable bang-bang mode for heater and set PWM limit
M140 H0 ; map heated bed to heater 0
M141 H2 ; map chamber to heater 2
M143 H0 S100 T0 ; set temperature limit for heater 0 to 100C
M143 H1 S280 T1 ; set temperature limit for heater 1 to 280C
M143 H2 S60 T2 ; set temperature limit for heater 2 to 60Cthank you
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Have you tuned the heater?
What firmware version?
You cannot disable the thermal watchdogs.
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This post is deleted! -
@Phaedrux
I Firmware is: 3.4.0beta7
I later changed config to M307 H2 A100 C10000 D2000 B1 S1.0 which kind of does the job, it doesn't throw errors anymore. -
@mr-igor-jef you're best off updating to 3.4.5 https://github.com/Duet3D/RepRapFirmware/releases/tag/3.4.5
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PID control is fine when you need tight temperature control and you have enough heater power to move the temperature quickly, neither of which is typical for a chamber heater. Just set it for bang-bang mode and it will work fine.
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So suppose I run firmware 3.4.5, I have my heater tuned (several times) and in 90% of cases all is fine. In the last 10% of the cases, the heater faults out during the initial stages of heating from cold to operating temperature (usually closer to the final temperature). The error is always something to the effect of 'the heating rate is lower than what is expected'.
Once operating temperature is achieved, the heater seems totally reliable.
M307 gives me R,D,E and K parameters to play with.
What parameter(s) should I tweak slightly (and in which direction) to signal the firmware that a slightly lower heating rate is ok while at the same time not messing with the perfectly working situation once the heater is at operating temperature?
As it happens, this is for the hotend and not the chamber heater but the question really applies to any heater.
Can I just reduce my R value a bit (which seems to primarily be relevant when the heater is cold but that is not where things fail) or will that screw with things at operating temperature.
My apologies if this post is seen as a thread highjacking - it is not meant to be and I think the question is relevant in the spirit of the original question.
