What sensor data is most critical for preventing thermal runaway in a 3D printer?

The most critical sensor data for preventing thermal runaway in a 3D printer is the temperature reading from the thermistor or thermocouple embedded in the hot end. Thermal runaway occurs when the hot end heater continues to heat up uncontrollably, potentially leading to dangerously high temperatures, melting of components, and even fire. The printer's firmware constantly monitors the hot end temperature using the thermistor. If the temperature fails to reach the target temperature within a specified time, or if the temperature continues to rise unchecked, the firmware detects a thermal runaway condition and shuts down the heater to prevent further escalation. Without accurate and reliable temperature data from the thermistor, the firmware cannot detect thermal runaway, making this sensor data essential for printer safety. Bed thermistor data is also beneficial, but less critical than the hot end.