It was the second substation fire in the area in two weeks. However, a utility company spokesman said the fire was not of the same magnitude of a July 4 fire which had prompted daily requests from power companies for customers to conserve electricity.
All but 13,000 homes and businesses initially left without power Tuesday had their power restored within two hours, said Damon Gross, spokesman for Arizona Public Service Co.
He said the fire damaged one of three transformers at a substation near 35th Avenue and Union Hills Dr.
He said APS had a replacement transformer.
No immediate word on what caused the fire.
The July 4 fire destroyed a bank of transformers at a substation that is one of four that distribute power in the Phoenix area for APS and the Salt River Project, the area's two major electrical utilities.
A replacement bank of transformers was expected to arrive Tuesday by barge in Los Angeles from the Northwest, then trucked to Phoenix starting Wednesday.
Traveling at 10 mph, APS said the 400,000-pound bank of transformers should arrive Saturday afternoon and be installed over the next three weeks.
Meanwhile, APS and SRP warned customers that demand was heading for a high this year as the temperature climbed to 109 and the humidity remained high. To avoid rolling blackouts APS reworked its transmission grid on Monday to increase the power demand it could handle.
