GEEK FREE
By Joe Callison
31 August 2018
(Archived)
Point of use surge protectors, usually in the form of a power strip, are probably used by most of us for at least some of the more sensitive or costly electronic items in our households. Did you know that your surge protector has likely been subjected to multiple surges if it is over two or three years old and may have diminished or even no protection left? If it has an indicating light, usually red, to indicate the protection is working, then there is at least some protection left in it. This is different than a light in the on/off or reset switch that only shows if it has power or not. Most surge protectors are designed to continue functioning as power strips even after the surge protection is gone, so if there is no indicating light for the surge protection status you have no way of knowing if it is providing any protection. To be safe, it should be replaced if more than three years old with one that has an indicating light for “protected”. Many also have an indicating light for “ground” to indicate that the receptacle it is plugged into is grounded properly, which is required in order for the full protection to function.
Other Types of Surge Protection
Electric utilities often offer an add-on service called “whole house” or “meter based” surge protection for a monthly fee. KCP&L offers meter-based surge protection plans ranging from $5.95 to $9.95 per month depending on how much replacement coverage you want included for damaged equipment. This type of protection installs behind your electrical meter on the outside of your house. It primarily provides protection for surges originating on the electrical supply line to your house, which is typically the source of less than half of all electrical surges. The rest are generated from within your house from electrical loads being switched on and off and motors starting and stopping. The external sources can create much larger surges than produced internally, but multiple smaller surges can still eventually break down sensitive electronic components and cause them to fail. The meter based surge protection will provide some protection from internal surges, but usually not at a low enough voltage to protect sensitive electronic components so they should still have plug-in surge protection. Equipment that does not have sensitive electronic components should be protected adequately by whole house surge protection.
Other whole house surge protector types are installed either inside or next to the power panel, usually by an electrician. To provide the best protection, these must be installed with minimal lengths of cable, otherwise a surge protector that limits surge voltage to 600 volts if directly connected to the panel may only limit surge voltage to 700 or more volts if located right next to the power panel. Plug-in surge protectors are available with 330V, 400V or 500V protection. Usually, the higher the voltage, the more surge it can absorb. The 400V level is adequate for most electronic equipment.
Limitations of Surge Protectors
Whether whole house or plug-in type, the most common surge protection provided uses electronic components that will break down from absorbing multiple surges. Whole house types are usually designed to handle enough surges that they should last at least 10 to 15 years for most homes. There are other types of surge protection based on power line filters that do not break down with multiple surges but are much more costly to purchase.
The electronic equipment most vulnerable to damage from electrical surges have both power and some type of low voltage signal connection, such as computers that have an Ethernet connection; televisions and other video equipment that may have an Ethernet connection, cable TV connection, or antenna connection; printers that may have an Ethernet or telephone connection; and answering machines that have an Ethernet or telephone connection. What makes them more vulnerable is that even if the power connection is on a surge protector, if the low voltage signal cable is not also protected by a surge protector, the equipment can still be damaged. Surge protectors are available either separately or built into some power strip type surge protectors for these types of signals. Wired Ethernet connections can often be avoided by using wireless Ethernet instead.
Most expensive appliances people are buying these days are loaded with electronics. Hopefully the manufacturers are including adequate surge protection for the electronics within the appliances since there are not usually separate power connections for the appliance motor circuits. Other concerns should be the proliferation of “smart” home controls and LED lighting that could be vulnerable to electrical surges.
No type of surge protector can protect against all possible electrical surges. A very close lightning strike can produce a higher energy surge than any practical surge protector can possibly handle. Disconnecting power to vulnerable electronics or expensive appliances before a lightning storm is not very practical, so maintaining an inventory of equipment with purchase receipts and dates for insurance purposes would be prudent. Also consider how important electronic data is backed up to prevent loss from a destructive surge that could destroy computer hard drives.
For more information on electrical surges in the home, I suggest the following:
https://www.nist.gov/sites/default/files/documents/pml/div684/Surges_happen.pdf
For guidance on buying surge protection equipment, I suggest the following:
https://thewirecutter.com/reviews/best-surge-protector/
https://shedheads.net/whole-house-surge-protectors/
For information on KCP&L meter-based surge protection:
https://www.kcpl.com/save-energy-and-money/home/protection/surge
