NEW YORK - Con Edison confirms to NY1 that a faulty connection led to that massive blackout in Manhattan earlier this month.

The company's preliminary investigation found that the relay protection system failed at a substation on 65th Street.

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The system is meant to detect electrical faults and adjust the power grid accordingly. 

Con Ed now says it has not only corrected the problem, but also put preventative measures in place at other substations.

During the blackout, more than 70,000 customers lost power in neighborhoods like Hell's Kitchen and the Upper West Side.

Power was also knocked out at several subway stations.