8:20 P.M. UPDATE: Danville Utilities has switched about two-thirds of customers to another substation after an issue in the Westover area, the city reports.
With the switch, there are still about 1,200 customers in the dark in the areas of Westover Drive from Woodlawn to the city limits, Riverside Drive from Spring Avenue to the city limits, and Berry Hill Road, Vandola Road, Moorefield Bridge Road, and Meadowview Ave.
The city is in the process of bringing in a mobile transfer unit to serve those customers, but that unit may not be in service until midday Tuesday.
ORIGINAL POST: A substation in Westover is out of service, the city reports, due to problems with two bad lightning arresters, which is the insulation used to protect the system from lightning.
Originally thought to take two to three hours to repair, city officials now believe the arrester has damaged a transformer bushing, another form of insulation, meaning it will take longer to fix.
Crews are still replacing the arresters, and the power hookup for some customers will be moved over to another substation during the outage.
For customers who cannot have their hookups moved, the situation could take as many as 12 or more hours to resolve. The outage affects more than 3,500 customers, the city reports.