JP3855-96 "General technical conditions for 3.6～40.5kV AC high voltage vacuum circuit breakers"
DL403-91 "Technical Conditions for Ordering of 10～35kV Indoor High Voltage Circuit Breakers"
It needs to be explained here: There is no special standard corresponding to my country's JB3855 in the IEC standard, but the "IEC56 AC High Voltage Circuit Breaker" is applied. Therefore, the standards of vacuum circuit breakers in my country are higher or stricter than IEC standards in at least the following aspects:
(1) Insulation level: Test voltage IEC China
1min power frequency withstand voltage (kV) 28 42 (between poles, pole to ground) 48 (between fractures)
1.2/50 impulse withstand voltage (kV) 75 75 (between poles, pole to ground) 84 (between fractures)
(2) The withstand voltage level of the vacuum interrupter fracture after the end of the electrical life test: not specified in IEC56. my country's JB3855-96 stipulates that the insulation capacity between the fractures of the vacuum circuit breaker after completing the electrical life test should not be lower than 80% of the initial insulation level, that is, the power frequency of 1min33.6kV and the impact of 60kV.
(3) Contact closing bounce time: IEC has no regulations, while my country's regulations require no more than 2ms.
(4) The test current of the temperature rise test: In the IEC standard, the test current is equal to the rated current of the product. my country's DL403-91 stipulates that the test current is 110% of the rated current of the product.
2. Main technical parameters of vacuum circuit breakers The parameters of vacuum circuit breakers can be roughly divided into two aspects: selection parameters and operating parameters. The former is used by the user when designing and selecting; the latter is the mechanical or kinematic characteristics of the circuit breaker itself, and is a technical indicator for operation and adjustment.
The following table shows the list of selected parameters, and takes the data of three types of vacuum circuit breakers as examples.
The parameters listed in the table must be verified item by item in the type test of the product according to the requirements of JB3855 and DL403 standards, and the final data shall be subject to the type test report.