Based on the previous focus on how reversed temperature sensor wiring in hot runner injection molding can be quickly diagnosed through heating verification and millivolt testing, the following typical symptoms will appear after the temperature sensor wiring is reversed:
Temperature Reverse Drift: When the hot runner actually heats up, the temperature value displayed by the temperature controller continues to decrease, completely deviating from the normal heating trend.
Hidden Minor Deviation: When the hot runner temperature is close to the ambient temperature, only a few degrees Celsius deviation occurs, without obvious alarm, making it difficult to detect directly.
Irregular Signal Jumps: Small, irregular jumps in temperature readings do not directly trigger an open circuit alarm and are easily misjudged as thermocouple aging.
Over-Temperature Runaway Alarm: The temperature control system continues to heat incorrectly, eventually causing the actual hot runner temperature to far exceed the set value, triggering an over-temperature alarm and leading to plastic decomposition and product edge scorching.
If any of the above symptoms occur, first check the positive and negative terminals of the temperature sensor wiring; there is no need to directly replace the thermocouple.
