Hotend Overheating

Brmatt

Every time i try and get my hotend to printing temperature (usually 210) it gets there no problem, but then it keeps going until it is stopped and cut off after going more than 15 degrees over the target temp. How can i fix this?

dc42

Have you run heater tuning?

Brmatt

Yes, did not seem to have any change. Maybe edit the P value?

Brmatt

@brmatt H I mean

dc42

Did you save the results of heater tuning? See https://duet3d.dozuki.com/Wiki/Tuning_the_heater_temperature_control. Also make sure that you don't have any M301 commands in config.g.

Brmatt

Here's what I get when I run auto tuning:
Warning: Heater 1 appears to be over-powered. If left on at full power, its temperature is predicted to reach 576C.
Auto tune heater 1 completed in 302 sec
Use M307 H1 to see the result, or M500 to save the result in config-override.g

Using M307 H1 gives me this information:
Heater 1 model: gain 551.9, time constant 199.1, dead time 4.7, max PWM 1.00, calibration voltage 0.0, mode PID, inverted no, frequency default
Computed PID parameters for setpoint change: P13.6, I0.442, D45.1
Computed PID parameters for load change: P13

Config.g doesn't have any M301 commands in it.

dc42

Did you copy those values into config.g, so that it contains the following?

M307 H1 A551.9 C199.1 D4.7 S1.0

Which Duet are you using? Unless it's a Duet 0.6 or 0.85, the calibration voltage shouldn't be zero.

Brmatt

@dc42 its a duet 0.85. Plugged in those values, I thought M500 did that automatically but I realized I misread. Running it again now, I'll report back.

dc42

@brmatt said in Hotend Overheating:

@dc42 its a duet 0.85. Plugged in those values, I thought M500 did that automatically but I realized I misread. Running it again now, I'll report back.

M500 will save the values to config-override.g. So if you have M501 at the end of config.g to load config-override.g, running M500 is sufficient.

Brmatt

@dc42 Yeah I guess I didn't have that in there. Putting it in manually worked perfectly. Heats up to the perfect temp. Thanks again man.