SURGE PROTECTORS
When there is too much electricity a surge protector is designed to absorb the overload and perhaps even die, to protect the devices plugged into it. Some surge protectors look like a power strip, but there is a big difference.
Over time, it is likely that any surge protector will eventually fail. What then? Some will continue providing un-protected power after they have failed. Others will cut off the power rather than leave you unprotected. You should know how any given model works before buying it. If its protecting devices that are not that expensive and thing is behind a lot of furniture, then maybe one that still provides power when the surge protection has failed, makes sense. Either way, it is important to get a model that has a visible indicator of whether it is providing protection or not. And, keep a cheat sheet of what a good indicator and a bad indicator are. It may be a light on vs. off or a different color for the indicator light. Also, a Ground indicator is good to have.
- As a rule, you get what you pay for with surge protectors. If you need to protect something very important or very expensive, than spend more for the surge protector.
- Surge protectors are sold based on Joules which is not the most important criteria. PenLight, a power company in the US, says "Joule ratings can be misleading ... Joule ratings are an unreliable measurement for determining a products surge capacity because there is no test standard. The Joule rating listed on a surge protector’s package is determined using an unknown method by the manufacturer." All that said, the more Joules the better. Wirecutter suggests only using a surge protector rated for 500 Joules or higher.
- What is a surge? There is no one answer, different devices kick in at different levels. The amount of extra electricity that is allowed is referred to as both the let-through voltage and the clamping voltage. The lower the let-through voltage, the better the protection. The lowest (best) UL 1449 rating is 330 volts. You may see devices rated for 400 or 500 volts. Wirecutter suggests that anything over 400 volts is bad.
- Clamping response time is how quickly the device responds to a surge. Faster is better. Nanoseconds (billionths of a second) are good. Picoseconds (trillionths of a second) are the best.
- If you can't get the above specs for any particular surge protector, it might be that the vendor does not want you to know them because they are poor.
- If Internet access is important, then, at the least, protect the modem and router with a surge protector. If Internet access is very important, then protect them with a UPS.
- Plug a surge protector directly into a wall outlet. Do not plug it into another surge protector or into an extension cord.
- It is best not to plug an extension cord into a surge protector
- No surge protector can hold a candle to lightning. If there is an electrical storm nearby, the safest thing to do is unplug your important or expensive devices.
- After a power outage, there is a chance the electricity may come back with a rush. The best thing to do in a power outage is to unplug your important or expensive devices while the power is off.
- When you will be away for an extended period, it is, again, best to unplug your important/expensive devices. This protects them from surges and lightning when you are not around and saves some electricity too.
- When buying a surge protector, the way it plugs into the wall outlet may be important in your home/office. Some plugs lie flat against the wall, others stick out a few inches. Among the flat plugs, some angle to the right, others to the left.
- Surges are not limited to electrical lines, they can also be carried by telephone lines and cable TV coaxial cables. Some surge protectors also offer protection for cable and telephone lines.
June 16, 2026: The Best Surge Protector by Sarah Witman for the Wirecutter. They recommend a Tripp Lite model that sells for about $60. Like most surge protectors that model needs to be replaced after 3 to 5 years. Their upgrade pick, however, should last forever. The upgrade model is the Furman Power Station 8 and it sells for about $110.
March 20, 2025: Misused Power Strips Cause a Lot of House Fires. Here’s How to Use Them Correctly. by Sarah Witman for the Wirecutter. The article explains how to tell a cheap power strip from an actual surge protector.
Also, assorted warnings about overloading a surge protector with a device such as a space heater. And recommendations on models to buy.