After nitrogen purging, the sensor must be dried and cooled to room temperature before performance testing. This is typically done within 6-7 hours after purging. Especially in the high-temperature and high-humidity environment of Wuhan, it is essential to ensure that low-temperature baking (60°C/4-6 hours) is completed and the sensor has cooled naturally before performance testing can begin.
1. Testing Timing: After the Purging + Baking + Cooling Closed Loop
Immediate Baking After Purging: Start low-temperature baking at 60°C within 30 minutes of purging and continue for 4-6 hours.
Natural Cooling After Baking: Cool to room temperature in a dry environment (approximately 30-60 minutes) to prevent condensation.
Final Testing Timing: Complete all procedures and begin testing within 6-7 hours after purging.
2. Required Test Items and Acceptance Standards
|
Test Item |
Acceptance Standard |
Test Tool |
|
Insulation Resistance |
>100MΩ (500VDC) |
Megohmmeter |
|
Loop Resistance |
2~10Ω |
Multimeter |
|
Zero-Point Calibration Offset |
<0.3℃ |
HMI System |
|
Power-On Stability |
No drift (<0.5℃/h), no burrs |
30-minute trial run |
Judgment Criteria: If any item fails to meet the standard, it is judged as recovery failure, and the sensor needs to be replaced.
3. Risks of Delayed Testing
Premature Testing (Without Cooling): Condensation may occur during the cooling process, resulting in a falsely low insulation resistance, which may be mistakenly judged as unrecoverable.
Delayed Testing (>24 hours): If not stored in a sealed container, the sensor may be exposed to moisture again, affecting the accuracy of the test.
