What is a Surge Protector?

A surge protector is an appliance that protects electrical devices from the voltage spikes power surges create. Even small power surges can inflict damage on your electrical fixtures over time. Installing a surge protector is an easy and relatively inexpensive way to keep your electronic devices safe from this damage.

Surge protectors are a very important home safety device. Not only do they help prevent surge-related burnout and electrical fires, but they’ll also help preserve your electrical fixtures and save you money. Here’s everything you need to know about the different kinds of surge protection, how they work, and why they’re important:

Why do I need a surge protector?

Protecting electrical fixtures and wiring from the damage inflicted by power surges has become such an important (and expensive) issue that the 2020 National Electrical Code now requires surge protection for all newly-installed residential service panels (article 230.67). While 230.67 doesn’t require surge protection on pre-existing service panels, it doesn’t make it any less important. Think about it: if surge protection was required on new panels, why wouldn’t it be just as important on older panels?

Large and small power surges happen for a wide variety of reasons, and they’re more common than you think. Even small, common surge protections can damage your fixtures or wiring over time. The more damage surges inflict, the faster your wiring and fixtures will wear down. Not only will this lower their usable life spans, but it could lead to dangerous sparking or malfunction. Surge protectors can protect against each type of possible power surge, preventing this damage.

How does surge protection work?

Surge protection defends your electronics against power surges. A power surge is an increase in voltage above the designated flow of electricity. Voltage is the difference in electric potential energy. Think of it as a measure of electrical pressure. When an increase in voltage lasts three nanoseconds or more, it’s a surge. When it lasts for one or two nanoseconds, it’s a spike. If either a surge or spike is powerful enough, they could seriously damage your electrical devices.

Surge protectors prevent this damage from happening in one of a few possible ways. A standard protector sends the extra, dangerous electricity into the grounding wire. Something called the metal oxide varistor (MOV) diverts the extra voltage. The MOV has three parts: a metal oxide material in the middle, a power line, and a grounding line. The metal oxide connects to the other two parts with semiconductors. The MOV diverts surge current but allows standard current to continue powering plugged-in devices.

What types of surge protection are there?

Power surges and spikes vary in behavior and point of origin. Different kinds of surge protectors are made to defend against these different threats. Here are different types of surge protectors you may want or need for you home:

Service entrance surge protectors

Service entrance surge protectors are the largest and most durable type of surge protector. They protect against destructive surges that originate from elsewhere on the power grid. Certified electricians install these surge protectors in front of your main service panel (at the electricity’s “service entrance”–hence the name). Once installed, all electricity entering your home will first pass through this protector.

Service entrance surge protectors are the “heavy duty” surge protectors. They guard against massive surges that even other surge protectors couldn’t handle. Installing service entrance protectors is a complex process because it involves turning off the power running to your home–not just the power in your home. If you’re interested in installing a service entrance surge protector, you’ll have to coordinate with a professional electrician and the local power company.

Whole house surge protectors

Whole house surge protectors are designed similarly to the service entrance surge protectors, but electricians install them inside your main breaker itself. If it’s properly installed, this type of protector can effectively guard against both large and small surges.

A whole house surge protector’s central location on the main breaker enables it to protect either a single circuit or all of the circuits in your home (hence the name “whole house” surge protector). Coordinate with a professional electrician to ensure your protector accomplishes what you want it to as effectively as possible.

Receptacle surge protectors

These surge protectors look similar to (but are not the same as) power strips. They’re probably the type you’re most familiar with. You can either purchase a simple, low-profile socket or models that look like a common outlet.

Receptacle surge protectors are an inexpensive option but they’re limited in functionality. Receptacle surge protectors can protect fixtures plugged directly into their outlets from small surges that originate inside the home, but nothing more. They do NOT protect against larger surges that come from outside the home. You should not consider a receptacle surge protector “complete” surge protection.

What type of surge protector should I have in my house?

What kind of surge protector you should install is specific to your situation. It’s important to do a little research before you buy one. Keep in mind that a power strip is not the same thing as a surge protector.

To make sure you’re purchasing a surge protector, look on the packaging for a joules rating—power strips don’t have this. Joules are a measurement for energy and will tell you how long the protector will work on your devices, depending on the strength of the surge. When you’re on the market for a surge protector, look for:

  • A High joules rating. The surge protectors joules rating is how much electricity it can safely redirect during a surge. You want it to be as high as possible. Look for a surge protector with at least a 600-700 joule rating.
  • A Low clamping voltage rating. The clamping voltage rating refers to the amount of voltage required to trigger the surge protector. Unlike the joules rating, you want this rating to be low. Even minor surges can be dangerous, after all. Look for a clamping voltage rating of 400 V or less.
  • A warranty. Sometimes surge protectors grant a warranty to the devices plugged into them if they fail to protect those devices during a surge or spike. Check the warranty to see what’s covered and what isn’t.
  • Professional installation. If you’re looking for service entrance or whole house surge protectors, you should contact a professional electrician. Experts will be able to install your surge protector correctly and make sure it works as effectively as possible.

Early Bird Electric recommends installing a whole house surge protector on all residential service panels. If you don’t have one (or don’t know if you have one), give Early Bird a call right away. Our experts will inspect your home service panel, tell you what we recommend and why, and get to work protecting your home from surges right away.