An Introduction to Surge Protectors and How to Choose One

by | Jul 17, 2023

Electronic devices comprise various components, including resistors, capacitors, transistors, diodes, and integrated circuits. These components are sensitive to changes in voltage and can be damaged by power surges. For example, a power surge can cause a computer to crash, erase important data, or even damage the motherboard. This is why surge protectors are often installed.

A surge protector is an electrical device that protects electronic devices from power surges. It diverts excess voltage from the device and into the grounding wire. In short, surge protectors are designed to absorb the extra voltage and prevent it from reaching your electronic devices. While not necessarily vital, it ensures your devices are safe from power surges. Few people know how they work, so we will discuss the details in this article.

How Surge Protectors Work

Surge protectors use one or more metal oxide varistors (MOVs) to redirect the excess voltage to the grounding wire. A MOV is a semiconductor device that has a variable resistance depending on the voltage applied to it. The MOV acts as a valve that opens when the voltage exceeds a certain threshold. When the voltage returns to normal, the MOV closes again.

Surge protectors also have a fuse or circuit breaker that will trip if the surge is too large. This protection prevents the MOV from overheating and catching fire. The surge protector will still work after the fuse or circuit breaker has tripped, but it will no longer protect from power surges.

The catch for surge protectors, however, is that the joules of protection are unpredictable. Surge protectors suppress joules based on a specific number. For example, a surge protector with a rate of 1000 joules can absorb 10 100-volt hits, 5 200-volt hits, etc. Once the surge protector has reached its maximum joule rating, it will no longer provide protection and may need to be replaced.

What Devices Need Surge Protectors?

A surge protector can benefit any electronic device plugged into an electrical outlet. However, some devices are more sensitive to power surges than others. For example, computers, televisions, and home theater systems are more susceptible to damage from power surges than lamps, fans, and other small appliances.

However, it’s worth noting that even devices less sensitive to power surges can still benefit from surge protection. Power surges can occur for various reasons, such as lightning strikes, power outages, or fluctuations in the electrical grid. These surges can damage or degrade the internal components of electronic devices over time and negatively affect the performance and lifespan of electronic devices.

Types of Surge Protectors

Two different types of surge protectors can be used on electronic devices. These include:

Power Strip Surge Protector

A power strip surge protector is designed to sit on a desk or mounted on a wall. It has multiple outlets that allow you to plug in multiple devices simultaneously. Some power strip surge protectors also have USB ports for charging smartphones and other devices.

Rack Mount Surge Protector

A rack mount surge protector is designed to be mounted in a server rack or other equipment rack. It has multiple outlets that allow you to plug in multiple devices simultaneously. Rack mount surge protectors are often used in data centers, server rooms, and other locations where multiple electronic devices are used.

Should You Get Surge Protectors?

As mentioned, surge protectors are not always necessary, but they can be beneficial in certain situations. A surge protector can provide extra protection if you have expensive electronic equipment that could damage power surges, such as servers, computers, or networking equipment. Additionally, if you live in an area with frequent power outages or electrical storms, a surge protector can help protect your devices from potential damage.

However, it’s worth noting that not all surge protectors are suitable for all electronic devices, and you must choose one compatible with your specific equipment. Additionally, surge protectors have a limited lifespan. They may need to be replaced every few years to maintain their effectiveness, so you must also conduct regular inspections to see if your surge protector still functions correctly.


Surge protectors protect your electronic devices against sudden power surges, especially if you frequently use them. While not necessarily a requirement for most devices, having one is an excellent precaution to prevent potential damage to your valuable equipment. All that matters is choosing thesuitablet surge protector for your specific needs and regularly maintaining and replacing it when needed to ensure its effectiveness.

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