Surge Protective Devices

In the Northeast and along the eastern seaboard, the sweltering, steamy days of Summer have returned with a vengeance. With these dog days comes sudden pop-up storms accompanied by fierce rounds of electrical discharge know as lightning.  Few things in the natural world are more awe-inspiring than an intense electrical storm, complete with brilliant flashes of lightning so bright they momentarily turn night into day followed by rolling peals of thunder that rattle dishes, our pets, and our nerves.  

However, there is another deadly side to these massive static events as they randomly search for pathways to ground. One lightning strike can generate between 30,000 and 50,000 amps (enough to power 60 homes for one day) and may contain enough explosive power equivalent to a ton of TNT. With that much charge, lighting can choose to go wherever it wants. Too often lightning bolts (negatively charged ions) find paths through objects in this quest for ground (positive ions) with devastating effects such as splitting trees or killing innocent people caught in the wrong place at the wrong time all within milliseconds. Lightning strikes have been responsible for numerous forest fires, home roof fires or worse, entering the home through various utility service inlets acting as ports (electric, phone and cable TV) wreaking havoc on unprotected electronic devices like televisions, computers, dimmers and so much more. Never has the need for protection been greater since the advent and popularity of smart homes.

Lightning may be the most common type of power surge but there are others. Power companies often unintentionally cause surges across their lines as they restore power after outages. Downed poles from car accidents are also known culprits.

How can a homeowner insulate and protect their greatest lifetime investment (both home and family) from this marauding, invasive forcE?


Surge suppression devices have been around for years and are commonly installed ahead of the point of use. Due to their ready access, power strips are frequently used by homeowners between the wall outlet and the sensitive electronic equipment. Not all surge strips are created equal and the truism “you get what you pay for” has never been more accurate in this case. Simply put, costly strips provide a greater degree of protection. But will a single power strip provide enough protection?

Experts in the defense of transient voltages recommend establishing as many layers of surge protection as possible in an effort to provide multiple walls of protection. Therefore, surge protective devices are now manufactured as Type 1, Type 2, and Type 3.


Typically, these whole house devices are permanently hard-wired into the main electrical panel either on the line side or load side. Advances in technology now provide LED green and red indicators (green for functional, red for non-functional). For example, the contents of a 10,000 volt SPD is half spent if it absorbs 5000 volts of in-coming transient voltage. If another strike were to occur, it would only be good up to and including 5000 volts.

Perhaps if you have an older SPD on your electrical panel but it is of an earlier generation without the LED indicator lights, the chances it has already performed as designed and is no longer functional is very likely. A consideration to have a new device installed is in order. Also, some of the installation methods of the past no longer meet with today’s electrical codes and need to be examined and replaced.


Type 2 TVSS devices are typically installed at secondary points of distribution, as in sub-panels feeding specifically sensitive electronic equipment. Many of these TVSS require a dedicated circuit breaker or overcurrent device and the location of this device must be ahead of the individual branch circuits it is being utilized to protect. Additionally, some circuit breaker manufacturers now produce duel functioning circuit breakers that act as both overcurrent protection and transient voltage surge suppression.


As discussed earlier, these are power strips installed at the point of power access (wall outlets) for cord and plug electronic equipment.

Thought should also be given to protect transient ingress voltage carried into the house via CATV lines and incoming telephone lines. Protective devices are available for these points of entry as well.

For a full analysis of your home electrical system with layering strategies for protection against unwelcomed transient voltages, call a Lippolis Electric specialist for a full house evaluation.


Lippolis Electric, Inc. | 538 Route 22, Pawling, NY 12564 | 845-855-1426 |