A southern New Jersey nuclear reactor has returned to service nearly four days after a problem on the non-nuclear side of the plant caused an automatic shutdown.

Officials say the Salem 2 plant started sending out electricity again on Tuesday morning. It initially was operating at 28 percent of its full power output, and was expected to return to full power by late afternoon.

Salem 2 went offline Friday, when an electrical problem caused a turbine trip. The turbine is powered by steam produced from water heated by the nuclear reactor, and the spinning of the turbine produces electricity.

Salem 2 is one of three reactors operated by PSEG Nuclear at its Artificial Island complex in Lower Alloways Creek Township. The other plants were not affected by the turbine problem.

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