Surge protective devices (SPDs) deliver a critical defensive function for equipment and systems used to run businesses by ensuring that power surges do not damage or destroy them. Usually, SPDs are designed to shunt damaging over-voltages to ground, or to sacrifice themselves to protect the connected equipment. Regardless of the specifics of the design, all SPDs have a useful life, after which they need to be replaced to continue to provide protection. An SPD may survive to protect your business for years - or only for a few days - depending on its exposure to surges. Let’s take a look at the possible life cycle of your SPD.

Purchase and Installation
Surge protective devices come in a range of varieties and sizes to provide the proper protection for different types of equipment and situations. For example, if your devices use Power over Ethernet, a PoE surge protector designed for the normal PoE 40 to 60 volt range will be required to protect the equipment while allowing data to pass through. Devices that use standard AC power will require an SPD designed for the 120 Volt range instead. Depending on the specific design of the surge protector, and certainly for any equipment that uses voltages higher than 120 volts, surge protection may need to be installed by a qualified electrician to ensure that it provides complete protection for your equipment. Surge protection and SPDs should be designed into the layout of any major electrical system, such as access control systems or surveillance systems.

Usage and Maintenance

SPDs may seem like a ‘set and forget’ method of protecting your business, and they may indeed protect your business for years at a time. Many SPDs are designed with a high threshold, so the lifespan of your SPD will depend on how often they are called upon to protect your devices, along with the severity of the applied power surges. There can be a significant variance as to how long an SPD lasts— an SPD installed fifteen years ago may still be in good condition, or it may suddenly need to be replaced after a large storm. It’s essential to plan for consistent, regular visual inspections of your SPDs, concurrent with other maintenance. Some SPDs are designed with visual indicators, such as LED lights, to alert you as to when a device is no longer functioning and needs to be replaced, but rarer—and more expensive—are the SPDs that can provide remote notification of surge protection status to your systems. Low voltage surge protectors may open a circuit when they’ve sacrificed, indicating that they need to be replaced when the device they protect no longer sends a signal—however, this may not be noticed in a timely manner due to human error. Visual inspection is a key part of the lifecycle of a surge protector.

Sacrifice and Replacement
An SPD has properly done its job when it sacrifices itself to protect your vital equipment. Usually this occurs after a power surge, originating from a nearby or distant lightning strike, internally-generated power spike, or other issue with your electrical system. Note that most electrical surges happen without being noticed, so installed SPDs may be subjected to many non-catastrophic surge events in the course of their lives. SPDs degrade over time as they absorb these non-catastrophic surges and may fail without an obvious warning. How often lightning is seen in your geographical area, and how often your facility sustains a power surge should be taken into consideration when deciding how often to inspect your SPDs, but they should be visually inspected at least every month to ensure that they’re still operational. Additionally, you should check your municipal requirements for surge protection to ensure that you remain within compliance with any relevant regulations.

The lifecycle of a surge protector may be days or years, but the job of an SPD is to dissipate over-voltage to ground and away from your equipment. When a surge protector goes end of life, it sacrifices itself.  Consistent inspections and replacement when sacrifice occurs is the best way to be sure that your critical business equipment is always protected from damaging surges.