Most people picture a lightning strike when they hear the word surge. Lightning is the dramatic case, but it is not the common one. Utility switching, grid faults, and large equipment cycling on and off all put voltage transients onto a property's wiring, and those happen year round.
Protecting a property against them is not one purchase. It works in layers, and the layers do different jobs.
Where surges come from
- Utility switching and faults on the distribution network
- Lightning, either a direct strike or a nearby strike coupling onto the service
- Large motor loads inside the property — air conditioning compressors, pool pumps, elevators in a shared building — starting and stopping
The last one surprises people. A share of the transients a property experiences are generated inside it, which is why protection at the service alone is only part of the answer.
Protection in layers
At the service
A device installed at the panel addresses what arrives on the incoming service before it reaches branch circuits. This is the layer that deals with the largest events.
At the equipment
Point-of-use protection sits at the outlet and covers a specific piece of equipment. It handles what gets past the first layer, and it is the layer that matters for sensitive electronics.
Neither layer replaces the other. A service-entrance device with nothing downstream leaves sensitive equipment exposed; point-of-use devices alone leave everything hardwired unprotected.
The part that decides whether any of it works
Surge protective devices divert energy to ground. That means their usefulness depends entirely on the grounding and bonding system behind them — if that is compromised, the device has nowhere to send the energy and the protection is nominal.
This is why an assessment starts at the grounding electrode system and the bonding, not at the product. It is also the part most often skipped.
What actually gets damaged
Surge damage is not always a dead appliance. More often it is cumulative — repeated small transients degrade components over months until something fails for no apparent reason.
- Air conditioning control boards, which are expensive and tend to fail at the worst time of year
- Appliances with electronic controls rather than mechanical ones
- Network equipment, televisions and computers
- LED drivers and lighting control systems
- Anything connected to both power and a data or coaxial line, since a surge can arrive on either
That last point is the one most often missed. Protection on the power side alone leaves an open path in through the data side.
Condominiums and shared buildings
A large share of South Florida properties are condominiums, and that changes the picture. The service equipment feeding the building is usually common property under the association's control, while everything past the unit's panel is the owner's.
That split matters twice over. It decides who can install protection at the service, and it means a transient arriving on a shared riser can affect several units at once. Owners can generally address their own panel and their own equipment; anything upstream is a conversation with the association, and usually with its own contractor.
Why this matters more in South Florida
Florida sees frequent thunderstorm activity through the summer months, and the Atlantic hurricane season runs from June 1 through November 30. Storm activity brings both direct events and the utility switching that follows outages and restoration.
Coastal properties have a second problem: salt air degrades grounding and bonding connections over time. A grounding system installed correctly years ago is not automatically still intact.
Reviewing what a property actually has
Worth knowing before buying anything: what protection is already installed, whether the grounding and bonding it depends on is sound, and which equipment justifies its own layer.
KRW Electric is a licensed electrical contractor (EC13012832) serving South Florida. See our residential electrical services, or get in touch to have the existing setup reviewed.
Reviewed by Kyle White, KRW Electric Company LLC — licensed electrical contractor EC13012832.
