Have you ever come home to find your digital clocks flashing "12:00"? It's caused by a power blink - a brief interruption that's designed to prevent a longer power outage.

Blinks occur when an obstruction, like a tree limb, comes into contact with a power line or transformer. To minimize the possibility of damage to the utility system or your home, a circuit breaker interrupts the flow of electricity for a fraction of a second.

If the limb remains on the line, the breaker opens and tries to reclose again. If the obstruction is still on the line after the third try, the breaker opens and does not reclose automatically.

At this point, a utility worker must be dispatched to remove the obstruction and manually reset the breaker.

Power blinks rarely cause damage to equipment. Older digital clocks and other devices are the most vulnerable to blinks; newer models are designed to ride out these small voltage fluctuations.

If you're experiencing frequent power blinks, call your electric company.

More from this category

Maintaining your electrical panel

Woman looking at circuit breaker

Learn what you need to do to keep your home's electrical system running at its best.

learn more

Updating electrical wiring

Electrician working on a circuit breaker

Yesterday's wiring seldom meets today's electrical needs. Learn what it takes to install modern wiring in an older home.

learn more

Power surges - cause & effect

Overloaded electric outlet

Lightning strikes are a common cause, but most power surges stem from inside your home.

learn more

Power quality 101

Mom and daughter on computer

From surge protector strips, to whole-house protectors - keeping your home safe.

learn more

Surge protectors

surge protector

Not all power strips protect against surges. Know what to look for to get your money's worth.

learn more

Get to know your service panel

Electrician working on a circuit breaker

Your fuse box or circuit panel is the heart of your home's electrical system.

learn more