NORTH PERRY, Ohio — The Perry nuclear power plant has been restarted and should be at nearly full power this weekend.
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Perry shut itself down a week ago after a digital control system mistakenly slowed down pumps that supply the reactor with fresh water — causing other safety systems to immediately — and without incident — shut down the reactor.
Engineering teams this week traced the problem to an interface, a kind of translator, between new digital controls and equipment in the plant’s original analog control system, said Jennifer Young, spokeswoman for Perry’s owner, the FirstEnergy Nuclear Operating Co. Modifications to the software in the digital system fixed the problem, she said.
The shutdown was unrelated to a problem in the same feed-water pump system in October that also led to an automatic shutdown. That problem was traced to a bad circuit board in a small inverter, or transformer, in the power circuits supplying electricity to the same pumps.
Read more at Perry nuclear power plant restarted, nearing 100 percent power
