I'm sorry if I didn't make this clear. I have seen whole house protectors and I have seen your 50,000 amp minimum figure. Here is what I don't know:
Lightning is maybe 20,000 amps. It is same whether the structure is a shack, a house, or an industrial structure. That amperage is about the surge; not about what a facility consumes from a utility. 50,000 is a minimum number. A 1970s IEEE paper put numbers to it. A direct strike to nearby AC wires, in rare cases, might be 100,000 amps. That means 40,000 amps via the primary protection layer. 20,000 amps to other homes, and 40,000 into yours. A 50,000 amps protector is sufficient even for something so rare that you may never see one in your lifetime.
Of course, if any protector fails (as reported by its indicator light), then that protector was doing near zero protection. And it was grossly undersized for that venue. (Grossly undersizing is why so many buy plug-in protectors.) Therefore a 100,000 amps protector is recommended.
Also useful is neighborhood history over decades. How many had surge damage how frequently? If surges occur much more often than every seven years, another reason to consider a 100,000 amps protector - and to upgrade another item that does protection.
Everybody has crappy power (hyped by advertising, spin, lies, and emotion). That is also perfectly ideal power once numbers are included. Best and worst is same when emotions describe anything. Appliances already make 'crappy' power into ideal power. To say anything more always - as in always - requires numbers. A fact most forget because they do not learn how to obtain numbers. Then that is proof that subjective (qualitative) judgements are sufficient. Above demonstrates how to make a preliminary conclusion using layman simple numbers.
If a home has this protection, and still suffers damage, then a human mistake must be identified. Damage created by a surge is due to a human mistake. That starts with the item that does protection - earth ground. Inspection is required. For example, is it single point earth ground? Does every wire in every incoming cable (telephone, coax TV, front security gate, lawn sprinkler, invisible fence, satellite dish) make a low impedance (ie less than 10 foot) connection to the same earthing electrode before entering? If not, all protection is compromised. Is any connect to a different earth ground, the household appliances can be damaged for the same reason that distant lightning strikes kill cows.
Simplest single point ground is two electrodes that are more than eight feet long. Some electricians will take one eight foot rod, cut it in half, and install both. Then neither are doing much. But he is richer.
Those electrodes must be firm. A loose rod often indicates a previous surge compromised a woefully insufficient installation. Geology is a major factor. For example one home had repeat lightning strikes to one wall. They earth lightning rods with an eight foot rod. Lightning struck that same wall again.
Those rods were only eight foot long in sand. That wall contained plumbing connected to deeper limestone. To connect to earthborne charges maybe four miles away, ligthning was using the better earthed item - plumbing. Longer electrodes were installed into deeper limestone. The lightning never struck that bathroom wall plumbing again.
Geology is another factor that is best learned and considered.
Some get so serious as to install an earthing system that surrounds the house. That has been routinely done even over 100 year ago where people were educated in science and where damage must never happen. So many Tech Notes demonstrates best earthing:
For example:
http://www.xantrex.com/documents/Discontinued-Products/SW2512MC-SW4024MC2UserGuide.pdf
Page 29 (Adobe page 37):
Figure 15 is the defective Multiple Point Ground System.
Figure 16 is an essential Single Point Ground System.
The first step in inverter protection is to make sure that all equipment in the system is physically grounded at the same location. This assures that there is no voltage potential between grounds in the system (See Figure 15 and Figure 16). No voltage means no current flow through the system.
Practically speaking, this would mean connecting the generator and battery grounds together, as well as the case or "safety" grounds in the system, and then attaching all to the same earth grounding rod.
Or
Tech Tips - Duke Energy
then select Tech Tip 8.
Demonstrated are good, bad, and ugly (preferred, wrong, and right) earthing solutions.
Another solved this critical earthing problem on a rocky mountaintop:
UFER grounding system
Or Tech Note 2 from: https://www.erico.com/catalog/literature/TNCR002.pdf
Even underground wires must be addressed in an earthing solution. Even underground wires are potential incoming surge conductors.
Any wire between two buildings must connect at both ends to both building's single point ground. Otherwise a lightning strike to one building is a direct strike to appliances inside the other. That first building acts like a lightning rod connected to appliances inside a second building.
No protector does protection. Best protection on a TV cable is a hardwire that connects low impedance (ie less than 10 foot) to that single point earth ground. More in a next post.
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