Temperature Curve Fluctuation Observation: Heat to the commonly used production temperature point of the hot runner and run continuously at a constant temperature for 2 hours. Observe the temperature curve of the Husky temperature controller:
Temperature fluctuation range ≤ ±1℃, with no irregular jumps or continuous unidirectional drift, indicates that basic operational stability meets the standard.
If random temperature jumps of more than 5℃ occur, it is highly likely due to loose wiring, ground loop interference, or poor contact of the thermocouple wires inside, indicating unacceptable stability.
Full-Link Hardware Troubleshooting and Verification: Check that the thermocouple terminals and compensating wire connections are secure, that the shielding layer is reliably grounded at one end, and that there are no multiple grounding points forming ground loops to avoid signal fluctuations caused by power frequency interference.
Measure the insulation resistance between the thermocouple poles and the shell; it should be ≥100MΩ to confirm that the insulation has not deteriorated and that signal drift will not be caused by leakage.
Thermal Cycling Stability Verification: After completing 5 heating-cooling cycles from room temperature to 600℃, the thermocouple readings returned to the initial reference temperature. The deviation from the initial value before the cycle was ≤ ±0.8℃, indicating that the thermoelectric characteristics did not undergo irreversible degradation under thermal cycling, and the long-term stability met the standard.
Interference Immunity Stability Test: Under the condition of high-power motors and frequency converters starting and running around the hot runner, the temperature display of the temperature controller was monitored. There were no random jumps or signal distortions, indicating that the interference immunity stability under electromagnetic environment was qualified.
