How To Install a Surge Protector

Video Sponsored by Square D

SPDs? You should get that checked out.

These days our homes seem to be spilling over with new technology and sensitive electronics, thus the surges of yesterday are only getting more and more costly. Most homeowners blame lightning for the majority of electrical surge damage to their home… but they’re being a bit misled. These voltage abnormalities more commonly come from large appliances in our homes (ACs, furnaces, air compressors etc.), rarely by lightning or changes to the power grid.  Surges shorten the life of sensitive electronics, the larger ones causing catastrophic damage to a homes electrical system. Surge Protection Devices or (SPDs) are devices installed at electrical services, branch circuits, or equipment that help protect against these sudden spikes in voltage, using special resistors to “sense” when higher-than-normal voltage is produced then immediately act to redirect voltage away from your electrical system. It’s important to note that surge protectors do not protect against lightning strikes to the home or building itself, that would be a lightning protection system which is something completely different, so get that out of your head right meow. To learn more about surges and how surge protection works, go check out Dustin’s deep dive into surge protection –>


In Dustin’s video you will see two different styles of Type 1 “whole home” Surge protection, the first being the snap-in, plug-on neutral style with no leads. This is a newer Square D design that only works with the corresponding QO plug-on-neutral panels. Not only is this style super sexy-sleek and convenient for the installer, but if installed correctly is as close to line as physically possible, meaning its rated efficacy is damn near 100%. Simply save two breaker spaces of the breaker bus and snap in the surge protector, the green LED light should come on indicating that it’s functioning and ready for surges…. and you’re done! Simple as apple pie and ice cream.

Square D Plug on Surge Protector

The second style is intended for more universal use, designed to be mounted to the exterior of any make and model of panel with a threaded nipple and lockring attachment that fits into a ½ inch knock-out at either the bottom or the side of a panel.  While this Type 1 is rated for use without an overcurrent protection device, for proper installation it is easiest to land the leads into a breaker that is installed at the nearest space possible to keep the leads short. If the panel being worked on has the option, this specific SPD is also rated to be directly wired to the phase bus mounting screws. When installing this style of SPD it is crucial to keep the leads as short as possible because with every foot of wire lead, 160 more volts is allowed to pass through to the load you’re trying to protect in the event of a surge.

Exterior mount Surge Protector 


An important feature to note about SPD’s is that they almost all come with a certain amount of Connected Equipment Coverage. These warranties provide a certain kind of “insurance” in the case property damage to a home’s electronics due to power surges and the failure of the SPD installed. Because each warranty is different, they should be fully read and understood before installation, be sure to follow all instructions thoroughly to keep the warranty intact and provide the best coverage.

Connected Equipment warranty 

Square D Surge Protection

The first surge protection device used in Dustin’s video is the QO250PSPD, a Type 1 SPD with the Surge Current Capacity of 50kA and a $50,000 warranty. This particular model is mounted inside the panel directly onto the highest point of the bus with a Plug-on-Neutral design. The second style is the  Square D HEPD80, a Type 1 whole home SPD with a Surge Current Capacity of 80kA and a $75,000 warranty.  Shneider equips their Square D surge devices with sizable warranties, some as high as $100,000 depending on the type and level of protection you choose. The Square D product line offers many Surge protection devices that differ in types, ratings, and installation styles to accommodate a wide range of residential buildings, look for a link to their website down below. 


Stay safe out there…Love from the ATX

Products use in this Video

Square D Plug On Surge Protector 

Square D Exterior mount Surge Protector

Fluke Voltmeter