TOKYO - Japan's Tohoku Electric Power Company on Wednesday restarted the reactor of Onagawa Nuclear Power Plant Unit 2, following the implementation of preventive measures after a technical issue with measurement equipment led to a temporary shutdown.

On Oct 29, the reactor was reactivated for the first time since the 2011 earthquake, but was shut down again earlier this month due to a malfunction that occurred while inserting measurement equipment into the reactor as part of preparations to resume power generation.

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The issue was traced to a loosened nut in the piping system, according to the company. After completing inspections, the reactor restarted at 9 am local time Wednesday.

The company plans to resume power generation by Nov 19, and begin full-scale commercial operations in December.

READ MORE: Onagawa nuclear reactor to restart in Japan's 2011 disaster-hit region

The Onagawa Nuclear Power Plant was seriously damaged in the March 11 earthquake and tsunami in 2011, losing most of its external power supply and experiencing flooding in underground facilities.

The reactor cleared safety screening in February 2020 under tougher post-Fukushima crisis safety standards and gained local consent to resume operations.

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The Japanese government has been pushing for reactor restarts to help secure energy in the resource-limited nation, though safety concerns about nuclear power persist among the public.