Computers and other modern electronic appliances have delicate components that can be affected by power surges. To protect your electronic appliances, we suggest installing quality surge protectors and unplugging electronic appliances during thunderstorms and power outages. Ordinary power strips will not provide the protection needed.

Power surges are common occurrences that may originate inside or outside your home or business. Inside, devices that require high levels of energy and cycle on and off can destabilize power quality—items such as elevators, air conditioners, refrigerators, motors, and power tools.

Outside, power quality on the electric grid can be affected by lightning, a downed power line, or equipment problems. In the case of lightning, its energy can also travel through phone and cable lines and damage your electronic equipment.

Damage from power surges can be repetitive and minor, gradually degrading components, or it can be sudden and catastrophic. There is no surge protection device that can provide 100% protection in the case of a severe power surge. You should not rely on a surge protector to protect medical equipment unless the device is specifically designed for that purpose.

There are two categories of surge protection devices, which can be used together.

1. Service entrance protection devices are mounted at or near the incoming electrical service line, telephone line, TV cable, and satellite dish cable.
2. Point-of-use protection devices are used with each electronic appliance and computer system.

Following are some buying tips for point-of-use surge protectors:

• The product should meet UL 1449 safety standards. Make sure the device is marked: UL Listed Surge Protective Device, or SPD.
• Purchase a device that protects all three electrical wires—hot line, neutral, and ground. Three-way protection is indicated L-N, L-G, N-G, meaning Line to Neutral, Line to Ground, and Neutral to Ground, respectively. And, you need to plug the device into a grounded outlet.
• Select a device with a low clamping voltage. For basic protection the device should not let more than 400 volts pass through to your equipment—330 volts provides good protection, and lower is even better. 
• Look for a device with an indicator light that tells you if the protective components are working, or buy one that will no longer conduct electricity if the components have failed.
• Look for a device that has thermal fuse protection to keep it from overheating.
• If buying a device to protect a computer, VCR, or TV, look for one that has jacks for phone and coax cable lines.
• Read the product’s warranty and equipment protection policy.