Unit 2 at the PPL Susquehanna nuclear power plant resumed generating electricity for the power grid on Friday.
The unit had been shut down since Dec. 16.
According to PPL, an electrical connection problem caused an automatic shutdown during a routine, scheduled turbine valve test. An unrelated issue with the positioning of a valve on one of the unit's main water pumps during start-up activities extended the out-of-service time.
"We have conducted a detailed review to understand the causes of these events and learn from them," said Timothy S. Rausch, PPL Susquehanna senior vice president and chief nuclear officer. "We have completed repairs, updated procedures and trained plant workers."
Unit 1 at PPL Susquehanna continues operating safely at full power.