Cause of transformer problem at Shippington nuclear plant still being determined

FirstEnergy officials are still trying to find the cause of a transformer problem which led to the unexpected shutdown of Unit 1 at Beaver Valley Nuclear Power Station in Shippington, Pennsyilvania, USA, on Monday. 

“We don’t expect to determine a cause of the transformer issue for at least a week,” said FirstEnergy spokeswoman Jennifer Young. “However, that information is not required before we conduct the repair or replacement, so we continue to move forward with preparation for that work.”

The main unit transformer, located on the generation side of the plant, converts power generated at the plant to the electrical voltage to distribute through the transmission system.
Workers at the plant are in the process of carrying out tests on the main unit transformer and will soon determine whether the transformer should be repaired or replaced, according to Young.

“A preliminary assessment indicates an electrical fault involving windings inside the transformer caused its failure,” said NRC spokesman Neil Sheehan on Wednesday. “That will have to be confirmed based on visual examination of the transformer’s interior.” Windings are part of the electrical coils inside the transformer.

“FirstEnergy might be able to repair the transformer. Other options include using one of two spare transformers on-site, but that one would require maintenance before it could be installed,“ added Sheehan.
Unit 1 will remain shut down until the transformer is operational and remain at 0 % power.

Source: TimesOnline