A tie breaker is accidently closed that parallels three single phase transformers each rated 500 kVA connected delta primary wye secondary, with a three phase 1500 kVA transformer connected delta-delta. The equivalent impedance of the delta transformer is 0.056 at an angle of 58o. The equivalent impedance of the wye transformers is 0.022 at an angle of 58o. Both transformer have 12.47kV to 480V. All feeder breakers are open. Calculate the magnitude of the current circulating in each transformer secondary, b) express the current in a) in percent transformer current for each transformer.
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A tie breaker is accidently closed that parallels three single phase transformers each rated 500 kVA...
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