I. Pre-Calibration Confirmation
Confirm that the measured RC parameters after calibration meet the following standards: filter cutoff frequency deviation ≤ 10%, target interference attenuation ≥ 20dB, and RC total time constant ≤ 200ms.
Confirm that the hot runner is currently in the process stability range, with no temperature jumps or oscillations for 30 consecutive minutes, and that the temperature control accuracy meets production requirements.
Record the final RC parameters after calibration (resistance value, capacitance value, filter cutoff frequency) and save them to the process parameter file as the locking benchmark.
II. System-Side Parameter Locking Operation
Enter the temperature controller's main menu, find the "Signal Filtering Settings" sub-option, and select "Dynamic RC Filtering Mode".
Switch the default "Automatic Adaptation" mode directly to "Manual Locking" mode, and enter the final RC benchmark parameters confirmed during this calibration in the parameter input box.
After submitting the parameters, select "Enable Hardware Latching". The analog switch of the dynamic RC network will be forcibly fixed at the current position by hardware, preventing the system from automatically switching parameters from the bottom layer.
Set an operation permission password, allowing only authorized process engineers to modify the lock status, preventing unauthorized personnel from accidentally altering parameters.
Return to the main interface and confirm that the status bar displays the "RC Hardware Lock" icon, indicating that the lock operation is officially in effect.
III. Hardware-side Anti-drift Reinforcement
Add a locking-type DIP switch to the hardware loop of the RC filter network. After calibration, directly switch to the locked position to physically disconnect the dynamic switching circuit, completely eliminating the hardware path for parameter drift.
Replace the ordinary resistors/capacitors in the RC network with high-precision, low-temperature drift components (temperature drift coefficient ≤25ppm/℃), reducing the probability of component drift at the hardware level.
IV. Anti-drift Verification after Locking
Continuously observe the production process for 2 hours, confirming that the temperature controller has no RC setting switching logs and that temperature reading fluctuations are ≤±0.5℃.
Simulate the maximum interference conditions in the field, confirming that the RC lock status has not been triggered or changed, and that the filtering performance is stable and meets the standards.
Add an RC lock status monitoring node to the MES system. Once an abnormal unlocking of the lock status occurs, immediately trigger a system alarm to detect risks at the first opportunity.
