M307 "bad model parameters" please help
-
I upgraded the firmware and I'm getting all the same results.
M307 results:
m307 h7 d60
Error: M307: bad model parametersTuning results:
m303 h7 s50
Auto tuning heater 7 using target temperature 50.0°C and PWM 1.00 - do not leave printer unattended
Auto tune cancelled because temperature is not increasing
-
Try replaving your heaters block with this, which I generated from the config tool. For some reason you have it skipped to heater7 when the next heater should be 5.
; Heaters M308 S0 P"bedtemp" Y"thermistor" T100000 B3950 ; configure sensor 0 as thermistor on pin bedtemp M950 H0 C"bedheat" T0 ; create bed heater output on bedheat and map it to sensor 0 M307 H0 B0 S1.00 ; disable bang-bang mode for the bed heater and set PWM limit M140 H0 ; map heated bed to heater 0 M143 H0 S120 ; set temperature limit for heater 0 to 120C M308 S1 P"e0temp" Y"thermistor" T100000 B4725 C7.06e-8 ; configure sensor 1 as thermistor on pin e0temp M950 H1 C"e0heat" T1 ; create nozzle heater output on e0heat and map it to sensor 1 M307 H1 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit M143 H1 S280 ; set temperature limit for heater 1 to 280C M308 S2 P"e1temp" Y"thermistor" T100000 B4725 C7.06e-8 ; configure sensor 2 as thermistor on pin e1temp M950 H2 C"e1heat" T2 ; create nozzle heater output on e1heat and map it to sensor 2 M307 H2 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit M143 H2 S280 ; set temperature limit for heater 2 to 280C M308 S3 P"duex.e2temp" Y"thermistor" T100000 B4725 C7.06e-8 ; configure sensor 3 as thermistor on pin duex.e2temp M950 H3 C"duex.e2heat" T3 ; create nozzle heater output on duex.e2heat and map it to sensor 3 M307 H3 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit M143 H3 S280 ; set temperature limit for heater 3 to 280C M308 S4 P"duex.e3temp" Y"thermistor" T100000 B4725 C7.06e-8 ; configure sensor 4 as thermistor on pin duex.e3temp M950 H4 C"duex.e3heat" T4 ; create nozzle heater output on duex.e3heat and map it to sensor 4 M307 H4 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit M143 H4 S280 ; set temperature limit for heater 4 to 280C M308 S5 P"duex.e6temp" Y"thermistor" T100000 B3950 ; configure sensor 5 as thermistor on pin duex.e6temp M950 H5 C"duex.e6heat" T5 ; create chamber heater output on duex.e6heat and map it to sensor 5 M307 H5 B0 S1.00 ; disable bang-bang mode for the chamber heater and set PWM limit M141 H5 ; map chamber to heater 5 M143 H5 S80 ; set temperature limit for heater 5 to 80C -
@phaedrux
This worked! I was able to tune correctly and the bad model parameters were probably that heater 7 shouldn't have existed. -
Glad that solved it.
-
This post is deleted! -
I spoke too soon. I tuned the heater with the thermistor pretty close to the heater because otherwise I kept getting the "auto tune cancelled because temperature is not increasing" error. So I moved the thermistor and was able to get it to tune, but then I moved the thermistor to above the print bed. After moving it when I tried to run the heater it would never get up to temp. So then I tried to re-tune with the better thermistor position and I got the auto tune error again and again.
I ultimately want the thermistor to be above the print bed for reasons but I cant get the heater tuned in that position.
-
@honeycris said in M307 "bad model parameters" please help:
I ultimately want the thermistor to be above the print bed for reasons but I cant get the heater tuned in that position.
Chamber heaters are usually pretty slow to heat the entire volume, so placing the thermistor far away from the heat source makes for a very loosely coupled heater control system. It's probably a better idea to have the thermistor closer to the heater so that it can actually be controlled. You'll just have to have a delay to wait a while for the temp in the chamber to rise and equalize.
-
Okay that makes a lot of sense. Thanks.
-
@honeycris alternatively, use a small fan (one that can stand the temperature in the chamber) to circulate air, so that the heat reaches the thermistor more quickly. This should also make it viable to use PID control.
-
can you give us some more details about the heater, chamber, and printer itself? Maybe with some more context we can give a better recommendation.
