The 8.25-kV circuit breaker in Table 9.4 can be used for rated fault current interruption of 33 kA at a rated 8.25-kV_LL system voltage. Determine the range of system voltage and interruption current it can be used for.

Table 9.4

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TABLE 9.4 Standard Ratings of Indoor Circuit Breaker in 4.76-38 kV Range Rated System Voltage KV LLrms 4.76 4.76 4.76 8.25 15 15 15 38 Rated Continuous Current kArms 1.2 1.2, 2.0 1.2, 2.0, 3.0 1.2, 2.0 1.2, 2.0 1.2, 2.0 1.2, 2.0, 3.0 1.2, 2.0, 3.0 Rated Symmetrical Fault Current Interrupt kArms 8.8 29 41 33 18 28 37 21 Rated Symmetrical Fault Current Interrupt MVArms (within K-factor)a 72.5 240 340 470 470 730 960 1380