This electrical fault also affected Unit 2 by causing breakers in the 230 kV switchyard to trip, cutting off power to RAT 2-B and vital bus "B." EDG 2-B subsequently started and restored power to the vital bus. At the same time, the electrical disturbance from the falling line striking the ground was detected by protective safeties on the Unit 2 main step-up transformer and a protective relay actuated, opening the transformer's output breaker. This caused a full load rejection to Unit 2, leading to a turbine trip and subsequently, a reactor scram. After Unit 2 tripped, the "B" non-vital electrical train lost power as it attempted to transfer from UAT 2-B (powered by the turbine generator) to the failed RAT 2-B, causing two of the reactor coolant pumps and one of the main feedwater pumps to trip. Despite this, plant cool-down proceeded safely. At 9:03 p.m., the RAT 2-B breakers in the switchyard were reset and offsite power was restored to the vital and non-vital "B" electrical trains, allowing reactor coolant pumps 2 and 4 to be restarted. EDG 2-B was shutdown. It was later determined that the fault disturbance caused by the line falling was not of significant magnitude to trip the protective relay per design and should not have caused Unit 2 to shut down. Further investigation found that current transformers on the main transformer were improperly set. The controls were adjusted to the proper setting. Had the CTs been properly set initially, the Unit 2 would have remained online.