Power blinks
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 prevent damage to the utility system or your home, a circuit breaker interrupts the electricity for a fraction of a second.
If the limb remains on the line, the breaker opens (power is interrupted) and tries to close again. If the obstruction is still on the line after the third try, the breaker opens and does not close 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.
Power surges
A power surge is a variation in electrical voltage. Power surges last less than 1/100th of a second and range in intensity depending on the situation.
Up to 80% of all power surges originate within the home - when devices with motors shut off or start up, diverting energy to and from other appliances. Common culprits of internal surges are power tools, refrigerators, printers and hair dryers. Smaller "everyday" surges can slowly destroy your expensive electric appliances - a process called "electronic rust."
External power surges are generally caused by uncontrollable events, such as lightning strikes, animals interfering with electrical equipment, and vehicle accidents with utility poles. Large power surges, such as lightning, can instantly ruin your TV, computer and other electronics.
Is Alliant Energy responsible for power surges?
Most surges are caused by factors outside of the control of telephone, cable and electric utilities. We are not responsible for surges that we do not cause, including those caused by lightning, animals, tree limbs, faulty wiring or surges created within your home.
How can I protect my home electronics from power surges?
The best way to prevent damage from power surges is to invest in high-quality surge protectors. All programmable appliances should be connected to a surge protector, including home entertainment systems, computer equipment and other digital devices.
Also remember that power surges can come into your home through other utility lines as well as electrical, so be sure to connect incoming cable and satellite TV lines, and all telephone lines, including fax and modem.