Vacuum Circuit Breaker Operating Mechanism Test

VCB Operating Mechanism The test of the operating mechanism is an important step to ensure that its mechanical and electrical properties meet the standards. The following are the main contents and steps of the operating mechanism test:

1. ‌Insulation resistance measurement‌
Use a megohmmeter to measure the insulation resistance of the opening and closing coils and the closing contactor of the operating mechanism to ensure that their insulation performance is good. The insulation resistance value should not be less than 1 MΩ‌.

2. ‌DC resistance measurement‌
Use a single-arm DC resistance bridge to measure the DC resistance of the opening and closing coils, and the test results should comply with the manufacturer's regulations‌.

3. ‌Minimum action voltage test‌
Test the minimum action voltage of the closing contactor and the opening and closing electromagnet of the operating mechanism to ensure that it can operate reliably within the range of 30%~65% of the rated voltage‌.

4. ‌Mechanical property detection‌
Measure the opening and closing time of the main contacts of the circuit breaker, as well as the synchronicity of opening and closing, to ensure that its action speed and synchronization meet the requirements‌.
Measure the bounce time of the contact when closing to avoid contact wear or failure due to long bounce time.
5. ‌Operating mechanism test‌
Perform an overall performance test on the operating mechanism, including the reliability and stability of closing and opening operations, to ensure that it can operate normally under various working conditions.
6. ‌AC withstand voltage test‌
Perform an AC withstand voltage test on the auxiliary circuit and control circuit of the operating mechanism to ensure that its insulation strength at rated voltage meets the standard.
7. ‌Test precautions‌
Safety should be ensured during the test, and fences should be set up and supervised by special personnel, especially during high-voltage tests.
After the test, the equipment should be fully discharged and all test data should be recorded for subsequent analysis and judgment.

Through the above tests, the performance and reliability of the vacuum circuit breaker operating mechanism can be fully evaluated to ensure its safe operation in the power system.