Electrical Surge Protection for Electrical and Electronic Equipment
Today more than ever, your world depends on electronics. Whether you are using a computer, watching TV, or charging a smart phone, the quality of your power is critical.
What Is a Surge?
A surge is a sudden, quick increase in voltage. Though usually small and unnoticed by you, over time these surges can damage sensitive electronic equipment. In an average home, these small surges can occur many times a day.
Can Voltage Surges Be Created by Equipment in My Home or Business?
Yes, refrigerators, freezers, furnaces, copier machines, laser printers, hair dryers, dishwashers, vacuum cleaners, and power tools—just to name a few—are responsible for creating surges.
What Other Situations Can Cause Voltage Surges?
Surges created by a storm or single lightning strike near your home can seriously damage electronics. Power lines and utility poles that are damaged by animals, fallen tree limbs, and car accidents can also cause surges. Surges can enter your home through telephone, CATV, or power lines.
What Can I Do to Protect My Equipment from Voltage Surge Damage?
You can start with installing a “circuit panel” or “service entrance” style surge protector (also referred to as a surge suppression device) in your home. This device either reduces electricity spikes, or stops them from entering the house all together. This will protect your larger appliances, such as ranges, water heaters, washers, dryers, dishwashers and motors. A qualified electrician or your local utility can ensure proper installation. Proper installation is key because even the best surge protector in the world is useless unless it is correctly installed.
But don’t stop here! To further protect your electronic equipment against surge damage, you need to install a surge protection device within fifteen feet of that equipment. This can be done with a simple plug-in unit or one that wires directly to your equipment.
The best way to protect yourself form surges is through the combination of service entrance surge protectors, and additional protection 15 feet from electronics.
Once I’ve Protected My Electrical Circuits, I’m Protected—Right?
Not necessarily. Damaging surges can enter your home through phone and cable circuits just as easily as power lines. The same rule applies as before: protect your phone and cable cords within fifteen feet of your equipment. At locations that combine electric power with either cable television or telephone, make sure that the surge protector protects everything.
Should I Be Concerned about the Quality of My Electrical Grounding?
Yes. A surge protection device is only as effective as the electrical grounding circuit that is made available to it. Surge protection devices divert surge current to grounding wires in your home and then ultimately to earth where they are safely diverted away from your equipment.
Since My Grounding Is So Important, How Do I Know If It Is Adequate?
A qualified electrician or your local utility can make that determination for you. Since most permanently wired surge protectors will require an electrician for installation, this may be a good time to have your grounding examined. Additionally, surge protection strips are only effective if used on three-prong (grounded) outlets.
Are All Surge Protectors the Same?
No. Like most products, surge protectors vary in quality. Careful attention must be paid to how a surge protector meets your requirements. Read the information on the box carefully and consult the checklist that follows.
What Should I Look for When Purchasing Surge Protection Products?
Look for surge protection devices that carry a “UL 1449” label. Surge protectors also carry a “joule” and/or “surge-current” rating. The higher the rating of these two categories, the better is the quality of the internal surge-stopping components. Another important performance characteristic is the “clamping voltage.” This is the voltage that the surge protector will let through to your equipment before it diverts it to ground (a lower clamping voltage is better—see checklist for recommendations). A quality device will have status lights that will display correct input wiring configuration and failure indicator lights or buzzers to signify whether the device is working properly.
How Much Should I Pay for a Surge Protection Device?
Expect to pay about $45–$100 for a higher quality eight-outlet plug strip with an internal phone protector. Stay away from those $8 specials. A residential circuit panel-mounted surge protector of higher quality will cost in excess of $100.
Do Surge Protectors Last Forever?
How Do I Know That It’s Time for a Replacement?
A variety of conditions can indicate that it is time to replace surge protectors. Two of the most prevalent signals are a failure indicator light going off and/or a buzzer sounding. Some surge protection strips are also designed to permanently turn off upon failure.
What Equipment Do I Have That Needs Surge Protection?
This first step in protecting your home is to conduct a walk-through inventory of your sensitive equipment. Then, determine which of the items that you want to protect. See the figure regarding whole house surge protection choices for examples of typical equipment that need surge protection.
Where Can I Get More Assistance in Purchasing Surge Protection?
Call your local utility first. Their personnel can provide information about proper selection, installation and use.
Surge Protector Checklist
- UL Listing (“UL 1449 Listed” is good. “UL 1449 Revision 2” is better).The following terms do not indicate adequate surge protection: “UL tested,” “meets UL,” and “UL.” The surge protector should indicate that it is “UL listed.”
- For a plug strip, the clamping voltage should be UL 330 volts, the surge-current rating should be at least 36,000 amps, and the joule rating should be at least 360 joules.
- For permanently installed surge protection, the clamping voltage should be no more than UL 400 volts, the surge-current rating should be at least 36,000 amps, and the joule rating should be at least 360 joules.
- Failure indicator light or buzzer
- Status light (for indicating proper wiring and grounding)
- Recessed on/off switch on strip surge protectors
- Multi-mode protection (line to neutral, line to ground, neutral to ground)
- Adequate plug spacing (wide enough to plug in power supplies if needed)
It is highly recommended that a surge protection device incorporate phone/modem and/or coax protection to cover all plug-in connections and any given piece of electronic equipment.
Surge Protector for TVs and VCRs should also include:
- Coax plugs
Surge Protectors for Computers, Telephones, and Telephone Answering Machines should also include:
- Telephone line plugs