Surge protector vs power strip — they are not the same thing
They look identical — a plastic strip with multiple outlets and a cord. Only one of them protects anything.
What a power strip actually does
A power strip is an extension cord with more outlets on it. It has a circuit breaker or fuse to protect against overload — too many devices drawing too much current — but it does nothing about voltage spikes. If a surge comes through the line, it passes straight through to whatever's plugged in.
What a surge protector actually does
A surge protector contains components called MOVs (metal oxide varistors) that absorb excess voltage and divert it away before it reaches your devices. This is what protects electronics from lightning-adjacent surges, grid switching spikes, and the jolt that happens when large appliances like AC units and refrigerators cycle on and off.
How to tell them apart
- Check for a joule rating. If a number like 600J, 1000J, or 2000J is printed on the box, it's a surge protector. Power strips don't have one because they don't do surge suppression.
- Look for UL 1449 certification. That's the safety standard specifically for surge protective devices. A plain power strip is certified under a different standard (UL 1363) that has nothing to do with surges.
- Price is a rough signal but not reliable — buy based on the joule rating and certification, not the sticker price.
Surge protectors wear out
Every time a surge protector absorbs a spike, its MOVs degrade a little. Most units don't tell you when they've used up their protection — they just quietly stop suppressing surges while still passing power through, so everything still turns on and you have no idea it's unprotected. Some models have an indicator light that shows protection status; if yours has one, check it after any major storm.
- Replace it after a major surge event — a nearby lightning strike, a rough outage/restoration — even if everything still seems fine.
- Replace it every 2–3 years as a baseline if there's no indicator light.
- A surge protector will not survive a direct lightning strike, and nothing plugged into a wall outlet will. Real lightning protection means a whole-house surge protector installed at your panel by an electrician.
Quick reference
- Power strip = more outlets, no surge protection
- Surge protector = has a joule rating and UL 1449 certification
- MOVs degrade with each surge — the protection has a shelf life
- Replace after a major storm, or every 2–3 years
- Neither protects against a direct lightning strike