Dear Jim: With all the electronic items I have, I thought about installing a whole-house electric surge suppressor. What are the various types, how can I compare the various models, and do they save energy? – Kerry K.

Dear Kerry: Today’s homes have more sensitive electronic devices than most people realize. Everyone thinks of televisions, computers or DVD players, but even most modern clothes washers and dryers, toaster ovens and other small appliances have sophisticated electronic components.

It is wise to install a whole-house voltage surge suppressor to protect entire branch circuits throughout your home. This does not eliminate the need for using a plug-in point-of-use surge suppressor for the most sensitive electronic devices. Using these two levels of protection is best.

Voltage surges in your home wiring actually are called transient voltage surges by professionals. There can be hundreds of these voltage spikes every day. They are very short in duration, but can exceed many hundreds of volts in magnitude. Instead of burning out the electronics with one surge, they typically slowly degrade components and wiring insulation. This causes the electronic device to fail prematurely.

There are many more sources of these voltage spikes than just lightning. If you live near commercial operations with large motors, such as large refrigeration units or pumps, surges occur when these motors switch on and off. Even the smaller motors in the clothes washer or vacuum cleaner inside your home can generate destructive surges throughout your house wiring.

Most whole-house surge suppressors use metal oxide varistor components that absorb the electrical energy from the surge when it gets above a certain level – the clamping voltage. Below this voltage, the surge suppressor has no effect. Some companies claim a surge suppressor can lower electric bills, but the primary purpose of one is protection.

If a very powerful surge comes through, it may burn out the surge suppressor and it must be replaced, but your electronic devices are saved. When selecting a surge suppressor, consider the manufacturer’s protection warranty. Some will replace any of your electronic devices, up to thousands of dollars, which are damaged by a surge that gets through.

The most common design of whole-house surge suppressor is mounted in the breaker panel. Another design is used as a base under the electric meter. If you are adding new circuit breakers, some include surge suppression.

When comparing surge suppressor specifications, larger maximum surge current and total energy dissipation are better. This means they can block a more powerful surge without being burned out. Generally a lower clamping voltage is better.

The following companies offer efficient surge suppressors: Control Concepts, 800-288-6169, www.control-concepts.com; Eaton, 800-386-1911, www.eaton.com; Intermatic, 800-391-4555, www.intermatic.com; Meter-Treater, 800-638-3788, www.metertreater.com; and Tytewadd, 800-383-6305, www.tytewadd.com.

Send inquiries to James Dulley, Bangor Daily News, 6906 Royalgreen Drive, Cincinnati, Ohio 45244, or visit www.dulley

.com.