The event at Oconee Nuclear Station was upgraded to an "Alert" classification Sunday when the fire that occurred damaged a power line in the station's switchyard, which resulted in an equipment fault.
The company said per procedure, an "Alert" must be declared when a fire causes loss of electrical equipment.
An "Alert" is the second in increasing significance of four nuclear emergency classifications.
This classification is used to describe conditions that require emergency response agencies to be in a heightened state of readiness, but pose no threat to public safety.
Earlier Sunday afternoon, an "unusual event" was declared at Oconee Nuclear Station due to a transformer fire in the Unit 1 switchyard at 3:20 p.m.
Unit 1 was safely shut down and Units 2 and 3 continue to operate safely.
The site fire brigade responded with assistance provided by local fire responders.
The fire was extinguished.
There is no impact to the power plant's neighbors or employees, according to a representative for the station.