The rationale behind the recalibration
The thermal conductivity of the inner hole wall and the tightness of the fit between the protective sheath and the wall are changed when the temperature detecting hole is repaired. As a result, the new heat transfer path is incompatible with the initial temperature adjustment settings. There would be a disparity between the shown temperature and the real temperature if the previous settings were still used, since this would lead to severe temperature measurement inaccuracies.
On-Site Quick Calibration Procedures
To make sure the thermal field is completely balanced, heat the hot runner system to the typical production temperature for the present product and keep it there for 30 minutes.
Make direct contact with the reference temperature sensor surface of the designated hot runner zone using a calibrated, high-precision standard contact thermometer. To execute single-point temperature compensation, enter the measured standard temperature value into the controller's calibration menu.
Initiate the PID auto-tuning feature of the controller to automatically adjust to the new sensor path's thermal response characteristics, hence removing temperature oscillation and overshoot problems.
After three cycles of heating and cooling to ensure that there is no signal drift and that the temperature variation is ≤±1°C, the calibration is finished.
After calibration, production may start up again right once, therefore avoiding injection moulding flaws brought on by inaccurate temperature measurements.
