Understanding Power Blinks

Learning

Have you ever noticed your lights blink during a thunderstorm? Or perhaps you’ve noticed a blinking microwave clock when you arrive home. When this happens, you’ve likely experienced a brief disruption to your electric service, which may have resulted from a power blink.

Power blinks are brief service interruptions typically caused by a fault (short circuit) on a power line or a protective device that’s working in reaction to a fault. Faults can occur through a variety of instances, such as squirrels, birds, or other small animals contacting an energized power line; tree branches touching a power line; or lightning and other similar events. .

When a fault occurs, a device called an oil circuit recloser (OCR) kicks into action — functioning much like a breaker in the electrical panel in your home:

  • First, the OCR opens to stop the fault, and then quickly closes again, resulting in a “blink” in power
  • If the disturbance on the line persists, the OCR will continue to operate or “trip” two more times and then remain open, resulting in a power outage

This is a safety mechanism that protects the system by cutting off power to the affected section of the line in order to isolate the problem until it can be repaired. Otherwise, the fault (and the resulting outage) could affect everyone on the entire substation feeder. 

While “blinks” may be a temporary aggravation, they are actually indicators that our system is functioning properly. The next time you experience a “blink,” be assured that our system is working as it should to ensure that as few members as possible experience any resulting outage.