======= PID Tuning =======
{{tag>about}}

[[Klipper]] uses a PID algorithm to maintain consistent heat for heaters like the nozzle and bed. These should be tuned initially and retuned any time the nozzle, hot end, thermistor, or heater element is changed. 

==== Klipper Docs ====

[[https://www.klipper3d.org/Config_checks.html#calibrate-pid-settings|Calibrate PID Settings]]


==== Wikipedia on PID ====

[[wp>Proportional–integral–derivative controller]]

==== Steps to PID Tuning ====

Execute the PID_CALIBRATE for the extruder with your typical print temperature, here we're using 220 as that's what we mostly print our PLA. Watch the extruder temperature settings and the graph while it takes a few minutes to evaluate how the heater performs. It will output three parameters. 

<code>
PID_CALIBRATE HEATER=extruder TARGET=220
// PID parameters: pid_Kp=21.037 pid_Ki=0.917 pid_Kd=120.698
// The SAVE_CONFIG command will update the printer config file
// with these parameters and restart the printer.
</code>

Add the three values to the EXTRUDER stanza in [[printer.cfg]]

<code>
[extruder]
control = pid
pid_kp = 21.037
pid_ki = 0.917
pid_kd = 120.698
</code>