Insulation resistance is a core performance indicator for hot runner thermocouples and directly affects signal stability, safety, and service life. Low insulation resistance leads to signal leakage, interference, and system failure.
High insulation resistance prevents the millivolt-level thermoelectric signal from leaking into the mold body or heater components. This ensures accurate temperature measurement and stable controller behavior.
In high-temperature environments, poor insulation accelerates signal attenuation and introduces electrical noise. This causes fluctuating readings, unstable heating, and inconsistent part quality.
Low insulation resistance often results from damaged cables, contaminated connectors, or moisture penetration. It may also indicate internal degradation of the mineral insulation in MI thermocouples.
Insufficient insulation can create safety risks by allowing high-voltage heater leakage to enter the low-voltage sensing circuit. This may damage the temperature controller or cause electric shock hazards.
Regular testing of insulation resistance helps identify deteriorating sensors before complete failure. Typical standards require insulation resistance above 100 MΩ at room temperature for reliable performance.
Maintaining high insulation resistance is essential for stable, safe, and long-lasting operation of hot runner thermocple systems.
