Electricity literally lights your way through the darkness, but it also supports every appliance, provides hot water through your water heater, and runs most entertainment activities within the home. 

As technology advances, so does your reliance on it. But technology needs a power source, and that’s electricity; whether it’s from external power companies or internal batteries.

Many devices are equipped with sensitive circuit boards and have limited protection against excess voltage. A single overvoltage can destroy everything from the refrigerator to computers to the water heater — and that can happen even if all of your home’s electrical installations are up to code.

An overvoltage happens when an electrical surge contains voltage that is too high. There are two main types of overvoltage:  External and internal.

External Overvoltage

External overvoltage is the one you tend to fear the most. A huge lightning strike or another huge power source reaches the home and damages your electronics and appliances. 

Although there are a lot of lightning storms in Texas, external overvoltage is only responsible for 20% of in-home power problems.


The overabundance of electricity is known as overvoltage. Voltage is the part of electricity that causes a physical shock (i.e. touching an electrical fence and getting knocked back). Amperes are the number of electrons that are present in an electrical source.

Standard fuses designed to protect equipment are rated at 20, 30, or 40 amps. If the electric shock is greater than this number, the circuit trips and stops the flow of electricity. In most cases, this works fine and protects human life. But it only takes .02 amps to be lethal.

A lightning strike may produce 200,000 amps of electricity. This is enough to jump across a burnt fuse and continue going. For this to happen, a lightning strike must strike within a mile of your home, and it usually needs to hit a power cable or other device to gain access to your electrical panel.

Utility Companies

Utility companies do everything that they can to fight off overvoltage, but nature is uncompromising. Downed power lines, repair on utility lines, and maintenance at local power stations can each cause an overvoltage.


Space? It may sound a bit far-fetched, but you may have heard about the solar flares that happen from time to time. They strike Earth hard about every 11 years. 

Solar flares and coronal mass ejection (CME) events send radiation in 8 minutes after being discharged from the sun. Most of these only affect the satellites in the ionosphere, but occasionally, Earth receives its share of magnetic storms.

Currently, these solar flares do not affect homeowners, but they can affect the main power grid during peak hours. If the main grid is already under pressure, the magnetic storm can cause transformers to explode, which passes bursts of electrical energy to homes.

Internal Overvoltage

Internal surges are not as dramatic as external ones, but they can be just as lethal to onboard circuit boards. Lights flickering every time the hairdryer or toaster turns on would be examples of internal overvoltage. This may not seem too terrible, and in most cases, it’s not.

However, 80% of overvoltage events happen from within the home. Every time those lights fluctuate or a circuit breaker trips because too many appliances are running at the same time, minor damage may occur. 

Most of the time, the damage done happens to the insulation surrounding the wiring, but the wiring itself can also become damaged.

Many homeowners feel like plug-in surge protectors are the cure, but every electrical installation technician will tell you that they really aren’t not. They may work well as a secondary backup, but to truly protect your home and appliances, you need a whole-home surge protector.

Providing Protection Against Overvoltage Events

There are many ways to protect your home against overvoltage events. The best way is to use multiple layers of protection. The first thing to do is contact an electrical installation expert at SALT Light & Electric for an inspection.

When we come out, previous electrical installations can be inspected for integrity and your wiring can be checked. It’s important to know the age, condition, and wiring schematic of your home before moving forward.

Whole-Home Surge Protection

A whole-home surge protector is your first line of defense against external voltage events. This surge protector is placed between the power lines and your electrical panel to catch high-voltage incidents before they enter your home’s wiring. An electrical installation expert is necessary to have this type of protection installed.

Electrical Subpanel

A subpanel’s main purpose is to isolate a specific area located further away from the main electrical panel, like a shop in the garage. It stops overvoltage events from the garage — or another space — from affecting your home. However, these can also be placed within the home to act as a secondary layer of protection.

Plug-In Surge Protectors

These devices are also called receptacle surge protectors, surge protector strips, and circuit protectors. They do not require an electrical installation technician to install. Before you buy one, though, look at them closely and verify they will do the job. 

Here are a few things to look for:

  • It should meet UL Standard 1449 (second edition)
  • It should provide a clamping voltage of 400 volts or less
  • It should absorb 600 joules of energy minimum
  • It should accept three-prong use
  • When damaged, it should stop working

Read the box or ask someone for help to make sure all of these criteria are met. Some units allow you to plug-in coaxial cables and phone lines for added protection.

Find the Best Electrical Expert Near Me

For almost 40 years, the team at SALT Light & Electric has provided electrical expertise to residential and commercial customers throughout central Texas. Whether you’re looking to further protect your home from electrical overvoltage events inside or outside the home or you’re in need of other electrical services, contact the experts at SALT Light & Electric today. We can help!