2)In the system below find: (kVA base = 1000) a. The X/R ratio for the 3-phase fault shown. (the small transformers X/R=10).(Hint: Reduce the R and X networks separately). (Assume X/R of the generator is: 40 and X/R of the motor is: 7 - IEEE C37.010) Ans: X/R total = 10.43 b. The symmetrical fault current Ans: 12,449 Amps c. The continuous current rating of the molded case breaker (standard rating) Ans: 350 Amps (IEEE 1015 Table 3-11) d. The interrupting rating of the molded case breaker. Ans: 20 KA (IEEE 1015 Table 3-25)

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