May 28, 2019 San Francisco Bay Area voltage sag at 7:11am


Tuesday May 28th, 2019 7:11am – Tuesday May 28th, the ongoing weather conditions in the San Francisco Bay area resulted in another voltage sag that affected customers throughout the region.  Grid voltage sagged to 73% of normal for 7.44 cycles, about 1/10 of a second. 

Figure 1 Voltage
Figure 2 Current

Customers reported no impact from this power quality event only on their sensitive loads and equipment. Currently, no utility root cause has been determined.

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