PID Tuning Bed Problems

kj3d

After waiting a crazy length of time I got the following message:

Warning: heater behaviour was not consistent during tuning
Auto tuning heater 0 completed after 3 idle and 25 tuning cycles in 29086 seconds. This heater needs the following M307 command:
M307 H0 B0 R0.084 C209.3 D32.90 S1.00 V24.1
Send M500 to save this command in config-override.g

So waiting for 8 hours plus to complete tuning cycle....

Any ideas of how to improve?

Started tuning cycle with: M303 H0 P1 S50 C2

Heated bed size is 1100 x 1050 with 1800watts of silicone heaters covering the whole area (Mains powered heaters)

It gets to the initial 50c temp in approx 4 minutes.

M115 response:

FIRMWARE_NAME: RepRapFirmware for Duet 3 MB6HC FIRMWARE_VERSION: 3.3beta3 ELECTRONICS: Duet 3 MB6HC v1.01 or later FIRMWARE_DATE: 2021-04-22 16:28:03

jay_s_uk

@kj3d just save the values and see how you get on.
I get that on one of my printers and it still works fine

Phaedrux

@kj3d said in PID Tuning Bed Problems:

Heated bed size is 1100 x 1050 with 1800watts

It's probably taking a very very long time to drop temp?

@kj3d said in PID Tuning Bed Problems:

Warning: heater behaviour was not consistent during tuning

It means that the heating and cooling rates didn't settle down to consistent values after several cycles. One possible reason is noise on the temperature sensor readings, which would be apparent in the temperature graph. What did the graph look like during tuning? What does it look like in normal use?

You can take the values it provided and manually tune them if you're not getting good results with them.

https://duet3d.dozuki.com/Wiki/Tuning_the_heater_temperature_control#Section_Setting_the_model_parameters_manually