Whether you’re watching Netflix at home or crunching numbers at the office, power surges are a reality that everyone has experienced. You might not know the cause, but you know the result all too well – lights out and devices damaged. In this blog, we’ll run through common causes of electrical surges and explain how to protect your home or office (or home office) from electrical surges.
What is an electrical surge?
Electrical surges, also known as electrical transients, are short bursts of energy that arise from sudden power changes to the electrical circuit. Surges can be caused by external or internal interference, such as high-energy devices powering on or lightning strikes that affect the entire grid.
To suppress the damage caused by spikes in electrical current, surge protection devices (SPDs) are able to divert a certain amount of surge current. This is represented by a rating in amperage (A/kA) or joules (J/kJ) that you’ll find listed on SPD devices.
Types of Surge Protection Devices
There are three common types of surge protection devices, each of which has its own purpose and application. It’s important to contextualize these devices by understanding how much current might come from a surge. It is reasonable to say that surges may run up to 10kA, though that number could be higher if the building experiences a direct lightning strike. Also, surge protectors degrade as they resist power fluctuations, so it is worthwhile to purchase units that exceed what’s necessary.
Type 1 Surge Protector
These devices are an intermediary between the municipal electrical grid and the service panel of your home or business. Type 1 surge protectors aid in filtering the power entering your building. This ensures that transients from external factors (such as lightning strikes or utility capacitor bank switching transients) are mitigated before entering your internal power system. These devices are often high-capacity, meaning they can withstand 100s of kA’s over their life and will typically alarm when it’s time to replace them.
Type 2 Surge Protectors
Type 2 Surge protectors are installed alongside the main service panel. These are effective in reducing surges caused internally or externally. They are intended to protect sensitive electronics on the internal electrical grid by reducing spikes in power caused by internal devices. They are useful in both commercial and residential environments (often called “whole home surge protectors”) and are far more capable at minimizing both large and small surges than Type 3 receptacle surge protectors (conventional power bars).
Given that Type 2 SPDs are used both commercially and residentially, the kA protection rating starts at around 50kA but can go up to around 1000kA.
Type 3 Surge Protectors
These are the most commonly seen type of surge protectors, often sold at department stores from a long list of brands. Due to the vast number of these units available, there is a wide range in terms of capability. Some are quite robust, able to redirect and protect against medium surges, while others are pitifully low and unable to anything more than a single mild surge.
These are the last line of defence. They should be used to supplement existing Type 1 and 2 SPDs, not to replace them. In fact, your cost to protect each device in your home or office with Type 3 SPDs would likely be much higher than a Type 2 SPD with a handful of Type 3 SPDs as needed.
High-current devices and appliances (such as dryers, water heaters, conditioners, refrigerators, etc.) can cause small surges in your home or office. External factors (such as lightning strikes or capacitor switching transients) may strike without notice and cause significant damage to electronics. Protecting against both types of surges is essential to reducing wear on your devices and preventing destructive surges.
