5 Reasons Why Your Surge Protector Might Fail

surge protector overload

Power surge protectors primarily protect your home electric appliances from power surges. When the appliances are not shielded, the resulting effects may be detrimental in the event of a power surge.

However, the power surge protectors do not guarantee full-time performance as they are also subject to malfunction. Here are the five reasons why your surge protector might fail.

The Surge Protector Is Worn Out

After some time of constant use, the surge protector will wear out. One which was installed more than ten years ago has definitely served its time and may not be doing much as far as protecting your electrical devices is concerned. The worn-out surge protector, therefore, imposes risks rather than offering protection.

A surge protector which has been in use for about that long should be replaced; it is likely to fail when exposed to the slightest power inconsistency. It may have failed already and gone unnoticed. You should, therefore, consider having it checked and replaced.

Degraded Metal Oxide Varistor (MOV)

When exposed to surges of various capacities, which often occur in different forms such as; small electrical charges occurring in large numbers or large electrical charges which occur in small numbers, the metal oxide varistor degrades. And this happens whenever the excess voltage is diverted to the MOV as a functioning procedure by the surge protector in ensuring your electrical appliances remain safe during a sudden rise in voltage. When the metal oxide varistor degrades, the surge protector will most likely fail, thereby letting all the current pass through, risking the safety of your devices.

Limited Performance Rating

Generally, various surge protectors have specific ratings beyond which, when surpassed, they may fail. The rating is done in joules, and a particular protector can absorb a given number of joules before its protection capability against the extra electrical energy runs out.

For instance, a surge protector rated 800 joules can absorb electrical energy surges of 100 joules eight times or 400 joules in two occurrences. After that, it ceases to be effective; thus fails. 

Your surge protector will only absorb the number of joules hits as per its rating. A surge protector which has experienced a higher number of surges is more likely to fail than that which hardly experiences the surges. Therefore, if your electrical system experiences power surges more often, then you will also need to replace the surge protector many times too. 


Surge protectors are likely to overheat due to damaged metal oxide varistors and semiconductors within their system. Overheating compromises the performance of the surge protectors, which may, in turn, result in their failure. Once you notice a significant rise in temperature of the surge protector, you should have it fixed immediately to avoid any further complications likely to develop from the heating situation.

Co-Ordination Failure

Surge protectors have different specifications for various models. Coordination failure occurs primarily due to matching different surge protector devices with non-concurring specifications regarding location, distance, and the type of standard exposure to elements within the power distribution systems. When there is coordination failure, the surge protectors may not function as required or still fail to operate entirely. Therefore, ensure the correct specifications are met with your installed surge protector devices’ stipulations for best performance.

It is easy to forget about your surge protector once installed, and it may be several months before you have a look at it or check whether it is operational. Also, determining if the surge protector is performing efficiently as it should be may not be easy. Some SPDs have installed lighting indicators that show performance status and can verify the operational status. At Wiring Pros LLC, we have a team of experienced professionals that can fix issues concerning your surge protector and other electrical problems. Get a Free Quote Today.