Excellent information on surges and surge protection is at:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
- "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE in 2005 (the IEEE is a major organization of electrical and electronic engineers).
And also:
http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Surges happen!.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology in 2001
The IEEE surge guide is aimed at people with some technical background.
The IEEE link was also posted by ChristTheGreat.
Did you read those Belkin specs? It does not even claim to protect from destructive surges. Its numbers define protection only from surges that typically do no damage.
Complete nonsense.
Many Belkin protectors even have protected equipment warranties.
Despite popular hearsay, one effective protector must protect everything in the house even from a direct lightning strike.
It is not possible to provide reliable protection from "a direct lightning strike" to a building without lightning rods.
Its spec numbers will say so. For example, lightning is maybe 20,000 amps. So a 'whole house' protector is rated at least 50,000 amps - so that even the protector is not damaged.
The author of the NIST surge guide looked at the surge current that could come in on residential power wires. The maximum with any reasonable probability of occurring was 10,000A per wire. That is based on a 100,000A lighting strike to a utility pole adjacent to the house in typical urban overhead distribution.
Recommended ratings for service panel protectors is in the IEEE surge guide on page 18. Ratings far higher than 10,000A per wire mean the protector will have a long life.
Facilities that cannot have damage always earth a 'whole house' protector.
Service panel protectors are a real good idea.
But from the NIST surge guide:
"Q - Will a surge protector installed at the service entrance be sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances [electronic equipment], No for two-link appliances [equipment connected to power AND phone or cable or....]. Since most homes today have some kind of two-link appliances, the prudent answer to the question would be NO - but that does not mean that a surge protector installed at the service entrance is useless."
Service panel suppressors do not by themselves prevent high voltages from developing between power and phone/cable/... wires. The NIST surge guide suggests most equipment damage is from high voltage between power and signal wires. An example of where a service panel protector would provide no protection is the IEEE surge guide example starting page 30.
Service panel protectors are very likely to protect anything connected only to power wires from a very near very strong lightning strike.
For protection, buy something completely different that, unfortunately, has the same name. More responsible companies provide these 'whole house' protectors. Including General Electic, Intermatic, Ditek, Siemens, Leviton, ABB, Square D, and so many other companies known by any guy for their integrity.
All these "responsible" manufacturers except SquareD make plug-in protectors and say they are effective. (Westom says plug-in protectors are a scam.)
SquareD says for their "best" service panel protector "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use."
It's easy to sell magic boxes to the naive.
They are only magic for westom. He can't figure out how they work.
The naive do not ask damning questions. For example, a protector adjacent to that router must either block a surge or absorb it. How does that 2 cm part block what three miles of sky could not? It cannot.
Of course not.
Protectors do not work by "blocking" or "absorbing".
As anyone who can read can find out in the IEEE surge guide (starting page 30), plug-in protectors work primarily by limiting the voltage from each wire (power and signal) to the ground at the protector. The voltage between the wires going to the protected equipment is safe for the protected equipment.
***When using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections, like coax also must go through the protector.
How does its hundreds of joules absorb a surge that is hundreds of thousands of joules? It doesn't.
Of course not.
The author of the NIST surge guide investigated how much energy might be absorbed in a MOV in a plug-in protector. Branch circuits were 10m and longer, and the surge on incoming power wires was up to 10,000A (the maximum that has any reasonable probability of occurring, as above). The maximum energy at the MOV was a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less.
Plug-in protectors with far higher ratings are readily available. High ratings mean long life. A plug-in protector, wired correctly (as above), is very likely to protect from a very near very strong lightning strike.
(Neither service panel or plug-in protectors protect by absorbing surges. They both absorb some energy in the process of protecting.)
If 30,000 volts can jump 2.5 centimeters, then how does that 2 cm protector part in a magic box stop 1 billion volts? Magic power strips will stop it? Even its specs do not claim protection from a typically destructive surge.
Complete idiocy.
At about 6,000V (US) there is arc over from service panel busbars to the enclosure. Since enclosure is connected to the earthing system that dumps most of the energy from a strong surge to earth. There is also arc over at about 6,000V at 15 and 20A receptacles (US). That is one reason the maximum energy measured at a plug-in protector was 35 joules.
Do not buy protectors defined by the NIST as "useless".
What does the NIST surge guide say about plug-in protectors?
They are "the easiest solution".
And "one effective solution is to have the consumer install" a multiport plug-in suppressor.
And "plug-in...The easiest of all for anyone to do. The only question is 'Which to choose?'"
Both the IEEE and NIST surge guides say plug-in protectors are effective.
Nobody said anything about 100% protection. But the IEEE says proper earthing provides "99.5% to 99.9% protection". Protection by earthing only one 'whole house' protector means a current need not hunt for earth inside; destructively via appliances. The IEEE then says, "Still, a 99.5% protection level will reduce the incidence of direct strokes from one stroke per 30 years ... to one stroke per 6000 years ... ".
The 99+% figures are from the IEEE "Green" book. They are for lighting rods. The have nothing to do with surge protectors.
Westom googles for "surge" in his compulsive crusade to rid the universe of the scourge of plug-in protectors. A significant part of this post is repeated from a post linked by TheMailMan78 from 2 months ago. Westom just ignores anything that conflicts with his limited beliefs about protection.