READING, Pa. -

Some Met-Ed customers in east Reading and Mount Penn spent part of their election night in the dark.

The utility notified its customers of a planned outage via Twitter:

"Reading customers: To make repairs to a substation, we must take it out of power at 10 pm for 30-60 mins. We apologize for the inconvenience."

About 3,000 homes and businesses were to be affected by the outage, which a Met-Ed spokeswoman said was expected to last about 30 minutes.