IEEE C37.09-2018 pdf download

IEEE C37.09-2018 pdf download.IEEE Standard Test Procedures for AC High-Voltage Circuit Breakers with Rated Maximum Voltage Above 1 000 V.
c) Time to the 50% value on the tail of the wave equal to 2500 jis ± 1500 .ts.
d) This waveform shall be obtained with the circuit breaker in the circuit.
c) When flashovers occur on the front of the wave, the peak voltage value is defined as the peak of the voltage wave that would have been obtained if no flashover had occurred.
4.5.8.2 Condition of circuit breaker to be tested
Switching impulse voltage tests shall be made with the circuit breaker mounted at an elevation above the ground plane not exceeding the elevation of the actual installation. Supporting frames shall be the same as those used in service: they shall be grounded and the exposed metallic surface area shall be no less than the area used in service.
Conductors shall be connected to both circuit breaker terminals, and unless specifically indicated otherwise. the connecting conductors shall be mounted horizontally. The diameter of these conductors shall not be more than that which is normally used in service. The conductors may be terminated in spheres or rings that have a diameter whose dimension in meters does not exceed an equivalent numerical value that is equal to the circuit breaker rated maximum voltage (in kilovolts) divided by 655.
No additional rings and shielding shall be employed if they are not a permanent part of the circuit breaker in its application.
4.6 Standard operating duty (standard duty cycle) tests
The standard duty cycle is demonstrated by test duty T 1 OOs of Table I.
4.7 Interrupting time tests
The interrupting time is established by adding the maximum contact opening time when measured at rated control voltage and rated operating pressure for mechanical operation to the maximum determined arcing time as calculated in Equation (1)j of the circuit breaker. The contact opening time of the circuit breaker shall be measured prior to the initiation of the short-circuit tests, under the pressures and control voltages specified in IEEE Std C37.04. The contact opening time corresponds to the elapsed time between the energization of the trip coil and the instant when the contacts separate.
The interrupting time of a circuit breaker is the maximum interval between the instant of initialization of the opening operation (i.e., energizing of the trip circuit) and the instant of interruption of the current in all three phases during terminal fault test duties T30, T60, and TlOOs specified in Table I under the following conditions:
— Rated auxiliary supply voltage and frequency
Rated pressures for operation, insulation, and interruption
The operating times of some circuit breakers may vary with the auxiliary supply voltage. To verify the interrupting time during these test duties, the maximum interrupting time should be amended to take account of the lower auxiliary supply voltage and pressures as follows:
If the maximum determined interrupting time (ii) max) found in this procedure exceeds the interrupting time, then the test duty that has given the longest interrupting time may be repeated with auxiliary supply voltage and pressure for operation and interruption at their rated values.
NOTE—The interrupting time during a make—break operation may be longer than that of a single-break operation for some circuit breaker designs. Such longer interrupting times may impact system protection strategy and stability if the delay is longer than the relay time. Users should advise the manufacturer of the maximum allowable interrupting time during make—break operations.
4.8 Short-circuit current making and breaking tests
4.8.1 General
The short-circuit current interrupting rating of a circuit breaker is demonstrated by a series of tests. These tests demonstrate the rated short-circuit current and the related required capabilities of the circuit breaker for applications in either effectively and noneffectively grounded systems.
The test duties used to demonstrate the performance of a circuit breaker are listed in Table I, where the test parameters are identified as follows:
a) Test voltage E takes different values depending on the test conditions for duties T 10 through TlOOa, where
I) The power frequency recovery voltage during breaking tests with as the first pole-to-clear factor and as the rated maximum voltage.