SeeMeCNC Rostock MAX v2 Assembly Manual page 231

A properly tuned PID look will result in a temperature display that looks similar to the example
below.
Fig. 22-13: Example of accurate temperature management.
The thin green line is the actual set point for the hot end (200C). You can see over time how the
actual temperature (thin red line) eventually merges with the center-line of the average temperature line
(brown line). This is a good representation of a well tune PID loop.
The graph at the bottom ("Output Extruder") measures how much power in percent that is being
fed to the hot end resistors. You can see how it applies 100% until it overshoots the target temperature.
It then falls to zero and then slowly ramps back up as the target temperature is maintained.
Rostock MAX v2 Assembly Guide
231