inventbox - Support

PID Tuning - Thermal Runaway Error

Using our powerful Radial Material cooler may cause the Heatblock to over-cool and you will get a Thermal Runanway Error message when printing. This is because of incorrect PID tuning.

We recommend you to let the material cooler run at 70-85% instead of 100%, otherwise it may cool too much and the adhesion between the layers will decrease. You can then increase performance to 100% when printing overhangs or when printing small parts at high speeds.

To adjust the extruder values, use Pronterface to enter the following commands:

M106 S204 (set cooler too 80%)
M303 E-0 S220 C8 (Start PID Tuning, chose Extruder 0, target temperatur 220 degree at 8 measuring cycles)

Now you wait until your console displays a message with the determined values like this:

bias: 91 d: 91 min: 206.48 max: 213.59
Ku: 32.59 Tu: 26.48
Classic PID
Kp: 19.56
Ki: 1.48
Kd: 64.72

Start Script

Paste this start script into your slicer.

G28 ; Home
( M851 Z-0.5 ; Z Offset * ) - only for manual Z Offset - overrides "Babystep" settings!
( M500 ; Save to Eprom ) - only for manual Z Offset - overrides "Babystep" settings!
G29 ; Level bed
......

* M851 Z-0.5 - Nozzle's distance to the bed at which the IR sensor should trigger. You can change this value according to how you set the IR sensor. If you have set the IR sensor to trigger a distance of 1mm from bed to nozzle, -1 must be entered here.